chore(deps): update dependency undici to v7.29.0 [security] by renovate[bot] · Pull Request #738 · microfleet/core

renovate · 2025-05-15T16:53:24Z

ℹ️ Note

This PR body was truncated due to platform limits.

This PR contains the following updates:

Package	Change	Age	Confidence
undici (source)	`7.3.0` → `7.29.0`

undici Denial of Service attack via bad certificate data

CVE-2025-47279 / GHSA-cxrh-j4jr-qwg3

More information

Details

Impact

Applications that use undici to implement a webhook-like system are vulnerable. If the attacker set up a server with an invalid certificate, and they can force the application to call the webhook repeatedly, then they can cause a memory leak.

Patches

This has been patched in https://github.com/nodejs/undici/pull/4088.

Workarounds

If a webhook fails, avoid keep calling it repeatedly.

References

Reported as: https://github.com/nodejs/undici/issues/3895

Severity

CVSS Score: 3.1 / 10 (Low)
Vector String: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici has an unbounded decompression chain in HTTP responses on Node.js Fetch API via Content-Encoding leads to resource exhaustion

CVE-2026-22036 / GHSA-g9mf-h72j-4rw9

More information

Details

Impact

The fetch() API supports chained HTTP encoding algorithms for response content according to RFC 9110 (e.g., Content-Encoding: gzip, br). This is also supported by the undici decompress interceptor.

However, the number of links in the decompression chain is unbounded and the default maxHeaderSize allows a malicious server to insert thousands compression steps leading to high CPU usage and excessive memory allocation.

Patches

Upgrade to 7.18.2 or 6.23.0.

Workarounds

It is possible to apply an undici interceptor and filter long Content-Encoding sequences manually.

References

Severity

CVSS Score: 5.9 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici has an HTTP Request/Response Smuggling issue

CVE-2026-1525 / GHSA-2mjp-6q6p-2qxm

More information

Details

Impact

Undici allows duplicate HTTP Content-Length headers when they are provided in an array with case-variant names (e.g., Content-Length and content-length). This produces malformed HTTP/1.1 requests with multiple conflicting Content-Length values on the wire.

Who is impacted:

Applications using undici.request(), undici.Client, or similar low-level APIs with headers passed as flat arrays
Applications that accept user-controlled header names without case-normalization

Potential consequences:

Denial of Service: Strict HTTP parsers (proxies, servers) will reject requests with duplicate Content-Length headers (400 Bad Request)
HTTP Request Smuggling: In deployments where an intermediary and backend interpret duplicate headers inconsistently (e.g., one uses the first value, the other uses the last), this can enable request smuggling attacks leading to ACL bypass, cache poisoning, or credential hijacking

Patches

Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.

Workarounds

If upgrading is not immediately possible:

Validate header names: Ensure no duplicate Content-Length headers (case-insensitive) are present before passing headers to undici
Use object format: Pass headers as a plain object ({ 'content-length': '123' }) rather than an array, which naturally deduplicates by key
Sanitize user input: If headers originate from user input, normalize header names to lowercase and reject duplicates

Severity

CVSS Score: 6.5 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici: Malicious WebSocket 64-bit length overflows parser and crashes the client

CVE-2026-1528 / GHSA-f269-vfmq-vjvj

More information

Details

Impact

A server can reply with a WebSocket frame using the 64-bit length form and an extremely large length. undici's ByteParser overflows internal math, ends up in an invalid state, and throws a fatal TypeError that terminates the process.

Patches

Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.

Workarounds

There are no workarounds.

Severity

CVSS Score: 7.5 / 10 (High)
Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici has CRLF Injection in undici via `upgrade` option

CVE-2026-1527 / GHSA-4992-7rv2-5pvq

More information

Details

Impact

When an application passes user-controlled input to the upgrade option of client.request(), an attacker can inject CRLF sequences (\r\n) to:

Inject arbitrary HTTP headers
Terminate the HTTP request prematurely and smuggle raw data to non-HTTP services (Redis, Memcached, Elasticsearch)

The vulnerability exists because undici writes the upgrade value directly to the socket without validating for invalid header characters:

// lib/dispatcher/client-h1.js:1121
if (upgrade) {
  header += `connection: upgrade\r\nupgrade: ${upgrade}\r\n`
}

Patches

Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.

Workarounds

Sanitize the upgrade option string before passing to undici:

function sanitizeUpgrade(value) {
  if (/[\r\n]/.test(value)) {
    throw new Error('Invalid upgrade value')
  }
  return value
}

client.request({
  upgrade: sanitizeUpgrade(userInput)
})

Severity

CVSS Score: 4.6 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici has Unhandled Exception in WebSocket Client Due to Invalid server_max_window_bits Validation

CVE-2026-2229 / GHSA-v9p9-hfj2-hcw8

More information

Details

Impact

The undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination.

The vulnerability exists because:

The isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15
The createInflateRaw() call is not wrapped in a try-catch block
The resulting exception propagates up through the call stack and crashes the Node.js process

Patches

Has the problem been patched? What versions should users upgrade to?

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

Severity

CVSS Score: 7.5 / 10 (High)
Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Undici has Unbounded Memory Consumption in WebSocket permessage-deflate Decompression

CVE-2026-1526 / GHSA-vrm6-8vpv-qv8q

More information

Details

Description

The undici WebSocket client is vulnerable to a denial-of-service attack via unbounded memory consumption during permessage-deflate decompression. When a WebSocket connection negotiates the permessage-deflate extension, the client decompresses incoming compressed frames without enforcing any limit on the decompressed data size. A malicious WebSocket server can send a small compressed frame (a "decompression bomb") that expands to an extremely large size in memory, causing the Node.js process to exhaust available memory and crash or become unresponsive.

The vulnerability exists in the PerMessageDeflate.decompress() method, which accumulates all decompressed chunks in memory and concatenates them into a single Buffer without checking whether the total size exceeds a safe threshold.

Impact

Remote denial of service against any Node.js application using undici's WebSocket client
A single compressed WebSocket frame of ~6 MB can decompress to ~1 GB or more
Memory exhaustion occurs in native/external memory, bypassing V8 heap limits
No application-level mitigation is possible as decompression occurs before message delivery

Patches

Users should upgrade to fixed versions.

Workarounds

No workaround are possible.

Severity

CVSS Score: 7.5 / 10 (High)
Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to cross-user information disclosure via shared cache whitespace bypass

CVE-2026-9678 / GHSA-pr7r-676h-xcf6

More information

Details

Impact

Undici's cache interceptor incorrectly classifies some responses as cacheable when the upstream Cache-Control header uses whitespace-padded qualified private or no-cache field names such as private=" authorization" or no-cache="\tauthorization". The parser preserves the surrounding whitespace, so later comparisons against the literal authorization field name fail and the response is stored.

In shared-cache mode, this allows a response containing one user's authenticated data to be served from cache to a subsequent caller, including an unauthenticated caller, when both requests resolve to the same cache key.

Affected applications are those that explicitly enable the cache interceptor (interceptors.cache()) in shared mode, forward Authorization headers upstream, and receive cacheable responses with non-canonical qualified private or no-cache directives.

Patches

Upgrade to undici v7.28.0 or v8.5.0.

Workarounds

If upgrade is not immediately possible, disable shared-cache mode for traffic that includes Authorization headers, avoid caching responses to authenticated requests, or add Vary: Authorization upstream.

Severity

CVSS Score: 5.9 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse

CVE-2026-6733 / GHSA-35p6-xmwp-9g52

More information

Details

Impact

Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests.

This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse.

Patches

Upgrade to undici v6.27.0, v7.28.0 or v8.5.0.

Workarounds

Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.

Severity

CVSS Score: 3.7 / 10 (Low)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici WebSocket client vulnerable to denial of service via fragment count bypass

CVE-2026-12151 / GHSA-vxpw-j846-p89q

More information

Details

Impact

The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service.

Affected applications are those using the undici WebSocket client (new WebSocket(...)) or the WebSocketStream API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint.

All releases starting at undici 6.17.0 are affected.

Patches

Upgrade to undici v6.27.0, v7.28.0 or v8.5.0.

Workarounds

No workaround is available. The fix must be applied through an upgrade.

Severity

CVSS Score: 7.5 / 10 (High)
Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to HTTP header injection via Set-Cookie percent-decoding

CVE-2026-9679 / GHSA-p88m-4jfj-68fv

More information

Details

Impact

undici's cookie parser in parseSetCookie percent-decodes cookie values via qsUnescape, turning encoded sequences like %0D%0A, %00, %3B, and %3D into their literal byte equivalents. RFC 6265 §5.4 does not specify any decoding and browsers do not decode either.

Applications that parse a Set-Cookie header and then forward the parsed value into a response header (proxies, middleware, SSR frameworks) become vulnerable to HTTP response header injection: an attacker-controlled upstream can inject arbitrary Set-Cookie, Location, or Cache-Control headers into the application's downstream response, enabling session fixation, open redirect, or cache poisoning.

Affected applications are those that use undici's cookie parsing (parseSetCookie, parseCookie, getSetCookies) and forward the parsed cookie value into a response header.

This was introduced in undici 7.0.0 via #3789.

Patches

Upgrade to undici v6.27.0, v7.28.0 or v8.5.0.

Workarounds

If upgrade is not immediately possible, do not forward values returned by parseSetCookie/parseCookie/getSetCookies directly into response headers; sanitize the value first to strip or reject CR, LF, NUL, ;, and = bytes.

Severity

CVSS Score: 5.9 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to Set-Cookie SameSite attribute downgrade via permissive substring matching

CVE-2026-11525 / GHSA-g8m3-5g58-fq7m

More information

Details

Impact

When undici parses a Set-Cookie header, it accepts any SameSite attribute value that contains Strict, Lax, or None as a substring, rather than the case-insensitive exact match specified by RFC 6265. Non-spec values are silently mapped to one of the three standard tokens:

SameSite=NoneOfYourBusiness is parsed as None, the most permissive setting.
SameSite=StrictLax is parsed as Lax, a downgrade from Strict.

Affected applications are those that consume Set-Cookie headers from server responses (for example via undici's fetch or proxy code paths) and then forward or rely on the parsed sameSite attribute. A malicious or non-compliant server can coerce the consumer's view of a cookie's SameSite policy to a weaker value, silently degrading the SameSite enforcement the cookie is supposed to provide.

This was introduced in undici 5.15.0 when the cookies feature was added.

Patches

Upgrade to undici v6.27.0, v7.28.0 or v8.5.0.

Workarounds

After parsing a Set-Cookie header, validate that the resulting sameSite attribute is one of 'Strict', 'Lax', or 'None' (exact, case-insensitive) before forwarding or relying on it.

Severity

CVSS Score: 3.7 / 10 (Low)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to cross-user information disclosure and parse-time crash via degenerate private cache directives

CVE-2026-13697 / GHSA-4cwx-7wf7-3272

More information

Details

Summary

Two issues in undici's cache interceptor, both fixed by the same patch on lib/util/cache.js:

Shared-cache disclosure: Responses with malformed qualified Cache-Control: private directives such as private="" or private="," can be incorrectly stored in the default shared cache, then served to a later caller with the same cache key.
Parse-time crash: Mixed unqualified-and-qualified private directives in the same header (such as public, max-age=60, private, private="hdr") cause an uncaught TypeError in the cache-control parser, terminating the request.

Impact

Shared-cache disclosure

Applications using interceptors.cache() in shared mode may cache a user-specific response and serve it to a later caller with the same cache key. This can disclose private response bodies and headers, including Set-Cookie.

Required conditions:

the cache interceptor is enabled in shared mode, including the default configuration;
an upstream returns a malformed directive such as Cache-Control: public, max-age=300, private="";
another request later matches the same cache key, without a separating Vary header.

Parse-time crash

Applications using interceptors.cache() against an upstream that returns a Cache-Control header combining unqualified private with qualified private="..." see an uncaught TypeError: output.private.concat is not a function during response handling. The request rejects; depending on the consumer's error handling, the process may exit.

Details

private="" is parsed as { private: [''] }. The shared-cache guard only rejects private === true, so the response can be stored. When served from cache, the previous user's body and headers may be returned to a different user.

For the crash variant, an unqualified private directive sets output.private = true, then a subsequent qualified private="hdr" directive attempts output.private.concat(['hdr']), which throws because boolean has no concat method.

The patch routes the qualified-directive path through a shared helper that normalizes empty-after-trim arrays to true and preserves existing true values, closing both vectors.

Patches

Upgrade to undici 7.29.0 or 8.9.0. Both releases fix the qualified private directive handling that caused the shared-cache storage and the parser crash.

Workarounds

Until patched, avoid shared interceptors.cache() for user-specific responses, use type: 'private', or disable caching for affected origins.

Credit

Disclosure variant reported by @h0rk1p via HackerOne report #3817497.

Severity

CVSS Score: 7.4 / 10 (High)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to downstream response desynchronization via retry interceptor

CVE-2026-16728 / GHSA-8xcm-r25x-g524

More information

Details

Impact

Undici's interceptors.retry() can deliver a response whose body length does not match the Content-Length header exposed to the application after a retry or resume of a partial response. Applications that use interceptors.retry() and forward upstream response headers and bodies downstream, for example proxy or gateway applications, may emit an invalid HTTP response with a stale Content-Length header. This can lead to downstream response desynchronization, connection hangs, or response corruption in clients or intermediaries that rely on the forwarded framing metadata.

A malicious or faulty upstream can respond to a range request with a 206 Partial Content response such as:

Content-Range: bytes 0-99/300
Content-Length: 300

and then send only 99 bytes before closing the socket. interceptors.retry() can then retry with Range: bytes=99-99, receive the final byte, and deliver a 100-byte body to the application while the response headers still contain Content-Length: 300 from the first response.

The bug requires interceptors.retry() to be enabled, an upstream that returns a partial response with a mismatched framing header, and a downstream forwarder that does not remove or recalculate Content-Length.

Patches

Patched in undici v6.28.0, v7.29.0, and v8.9.0. Users should upgrade to one of these versions or later.

Workarounds

Disable interceptors.retry() for untrusted upstreams.
Remove or recalculate Content-Length before forwarding a response body assembled or transformed by Undici.

Severity

CVSS Score: 4.8 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields

CVE-2026-16729 / GHSA-v3r7-h72x-cjcm

More information

Details

Impact

The setCookie function has two attribute injection paths. validateCookieDomain does not reject semicolons (validateCookiePath already does at 0x3B), so a domain value like example.com; SameSite=None lands verbatim as Domain=example.com; SameSite=None. The unparsed array's loop only checks each entry contains = and does not sanitize values, so an entry like X-Custom=val; HttpOnly lands unchanged, injecting HttpOnly without the caller setting cookie.httpOnly = true.

Applications that pass user-controlled input to these fields, typically multi-tenant or reverse-proxy servers that scope session cookies to a tenant-supplied domain, can have SameSite CSRF protections bypassed, Secure or HttpOnly forced or stripped, or the intended SameSite tier overridden.

Patches

Patched in undici v6.28.0, v7.29.0, and v8.9.0.

Workarounds

Sanitize domain values against the RFC 1034 letter-digit-hyphen set before passing to setCookie.
Do not pass user-controlled data to the unparsed field.

Severity

CVSS Score: 4.8 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to cross-user information disclosure via whitespace around equals in Cache-Control directives

CVE-2026-14643 / GHSA-jr45-8vmc-qm54

More information

Details

Impact

Undici's cache interceptor mishandles optional whitespace (OWS) placed around the = of a qualified no-cache or private Cache-Control directive, such as no-cache ="authorization" (OWS before =) or no-cache= "authorization" (OWS after =). The parser either drops the directive entirely or stores a field name with literal quote characters, so the downstream cache decisions do not recognize the qualification and the response is stored.

In shared-cache mode, this allows a response containing one user's authenticated data to be served from cache to a subsequent caller, including an unauthenticated caller, when both requests resolve to the same cache key. The impact class is identical to CVE-2026-9678 (GHSA-pr7r-676h-xcf6); this advisory covers the whitespace-around-= bypass that the earlier fix did not normalize.

Affected applications are those that explicitly enable the cache interceptor (interceptors.cache()) in shared mode, forward Authorization headers upstream, and receive cacheable responses with qualified private or no-cache directives whose field-name list is padded with OWS around the =.

Patches

Upgrade to undici v7.29.0 or v8.9.0.

Workarounds

If upgrade is not immediately possible, disable shared-cache mode for traffic that includes Authorization headers, avoid caching responses to authenticated requests, or add Vary: Authorization upstream.

Severity

CVSS Score: 5.9 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

undici vulnerable to CRLF Injection via blob-like body 'type' property

CVE-2026-15157 / GHSA-m8rv-5g2x-5cg5

More information

Details

Impact

When an application passes a duck-typed blob-like body to undici's HTTP/1.1 dispatcher (via request(), stream(), pipeline(), or dispatch()) with a .type derived from untrusted input, an attacker can inject CRLF sequences (\r\n) to append arbitrary HTTP headers and potentially smuggle a second request past the upstream.

The vulnerable branch in lib/dispatcher/client-h1.js pushes body.type directly into the outgoing headers with no validation, while every other header path in undici goes through isValidHeaderValue():

} else if (util.isBlobLike(body) && request.contentType == null && body.type) {
  headers.push('content-type', body.type)  // bypasses isValidHeaderValue()
}

The bug requires a hand-rolled duck-typed blob object or a Blob subclass with a controlled .type. Native Blob is safe because its constructor strips CRLF from .type. fetch() is unaffected because it validates via the Headers class. Ecosystem consumers that build duck-typed blob shapes from user input include form-data-encoder, formdata-polyfill, and formdata-node.

Same defect class as CVE-2022-35948 (explicit content-type sink, fixed in undici 5.8.2) and CVE-2026-1527 (upgrade option sink, fixed in 6.24.0 / 7.24.0), both closed by adding isValidHeaderValue() on their respective sinks. This branch was missed.

Patches

Patched in undici v6.28.0, v7.29.0, and v8.9.0. Users should upgrade to one of these versions or later.

Workarounds

Set an explicit, validated content-type header on the request options (skips the vulnerable branch).
Use a native Blob (or fetch-blob) instead of a hand-rolled duck-typed object.
Reject control characters in the MIME type before assigning it to .type.
Use fetch() instead of the non-fetch APIs.

Severity

CVSS Score: 4.2 / 10 (Medium)
Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N

References

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

Release Notes

nodejs/undici (undici)

⚠️ Security Release

This release line addresses 7 security advisories, all shipped in v7.28.0.

Action required: Upgrade to undici 7.28.0 or later.
npm install undici@^7.28.0

The v7 line is not affected by GHSA-38rv-x7px-6hhq (CVE-2026-9675), which is
an 8.x-only regression.

Note on GHSA-hm92-r4w5-c3mj: this fix shipped in v7.28.0, not the
earlier 7.2x line — the vulnerable single-pool code was still present through
v7.27.2. The per-origin pool fix is
3805b8f8 (#5041).

Summary

Advisory	CVE	Severity (CVSS)	Fixed in	Fix commit
GHSA-vxpw-j846-p89q	CVE-2026-12151	High (7.5)	7.28.0	`8cb10f98`
GHSA-vmh5-mc38-953g	CVE-2026-9697	High (7.4)	7.28.0	`04201f89`
GHSA-hm92-r4w5-c3mj	CVE-2026-6734	High (7.5)	7.28.0	`3805b8f8`
GHSA-pr7r-676h-xcf6	CVE-2026-9678	Moderate (5.9)	7.28.0	`85a24055`
GHSA-p88m-4jfj-68fv	CVE-2026-9679	Moderate (5.9)	7.28.0	`d0574cc4`
GHSA-g8m3-5g58-fq7m	CVE-2026-11525	Low (3.7)	7.28.0	`d0574cc4`
GHSA-35p6-xmwp-9g52	CVE-2026-6733	Low (3.7)	7.28.0	`ea8930cf`

High severity

WebSocket DoS via fragment count bypass — CVE-2026-12151

GHSA-vxpw-j846-p89q · CWE-400, CWE-770
Fix: 8cb10f98 websocket: limit the number of fragments in a message (part of backport a027a4a0 Backport WebSocket maxPayloadSize fixes to v7.x, #5423)

A malicious WebSocket server can stream a large number of small or empty
continuation frames. Undici enforced a limit on cumulative payload size but did
not limit the number of fragments per message, leading to unbounded memory
growth and denial of service.

Affected: applications using new WebSocket(...) or WebSocketStream
against untrusted endpoints.
Workaround: none — upgrade is required.

TLS certificate validation bypass in SOCKS5 ProxyAgent — CVE-2026-9697

GHSA-vmh5-mc38-953g · CWE-295
Fix: 04201f89 fix: honor requestTls when proxy is SOCKS5 (#5417)

The ProxyAgent silently discarded the requestTls option when configured with
a SOCKS5 proxy. TLS connections through the SOCKS5 tunnel ignored user-configured
parameters such as ca, cert, key, rejectUnauthorized, and servername,
falling back to the default Mozilla CA bundle. Applications relying on
certificate pinning to an internal CA were exposed to man-in-the-middle attacks.

Affected: ProxyAgent / Socks5ProxyAgent over SOCKS5 that rely on
requestTls.
Workaround: route traffic through an HTTP-proxy ProxyAgent, where
requestTls functions correctly.

Cross-origin request routing via SOCKS5 proxy pool reuse — CVE-2026-6734

GHSA-hm92-r4w5-c3mj · CWE-346
Fix: 3805b8f8 fix(socks5-proxy-agent): use per-origin pools to prevent cross-origin routing (#5041)

Socks5ProxyAgent reused a single connection pool across different origins
without verifying the pool's origin matched the requested origin. This could
route credentials and request data to unintended destinations, cause responses
from the wrong origin to be trusted, and enable HTTPS→HTTP downgrade.

Affected: applications using Socks5ProxyAgent across multiple origins
(introduced in 7.23.0 via #4385).
Workaround: use a separate agent instance per origin.

Moderate severity

Cross-user information disclosure via shared cache whitespace bypass — CVE-2026-9678

GHSA-pr7r-676h-xcf6 · CWE-524
Fix: 85a24055 fix(cache): trim qualified field names

The cache interceptor mishandled responses with whitespace-padded
Cache-Control directives such as private=" authorization". In shared-cache
mode this could cause authenticated data to be cached and served to other users.

Affected: apps using the cache interceptor in shared mode that forward
Authorization upstream and receive non-canonical qualified directives.
Workaround: disable shared-cache mode for authenticated traffic, avoid
caching authenticated responses, or add Vary: Authorization upstream.

HTTP header injection via Set-Cookie percent-decoding — CVE-2026-9679

GHSA-p88m-4jfj-68fv · CWE-93
Fix: d0574cc4 fix(cookies): preserve values and parse SameSite strictly

parseSetCookie applied percent-decoding to cookie values, turning encoded
sequences like %0D%0A and %00 into literal bytes, contrary to RFC 6265 §5.4
and browser behavior. Applications forwarding parsed Set-Cookie values into
response headers were exposed to header injection, enabling session fixation,
open redirects, and cache poisoning. Introduced in 7.0.0 via
#3789.

Workaround: sanitize values before forwarding — strip or reject CR, LF,
NUL, ;, and =.

Low severity

Set-Cookie SameSite attribute downgrade — CVE-2026-11525

GHSA-g8m3-5g58-fq7m · CWE-183
Fix: d0574cc4 fix(cookies): preserve values and parse SameSite strictly

The cookie parser accepted SameSite values containing Strict, Lax, or
None as substrings rather than requiring exact matches per RFC 6265. Values
like SameSite=NoneOfYourBusiness parsed as None, and SameSite=StrictLax
parsed as Lax, silently weakening cookie security policies for apps that
forward parsed attributes.

HTTP response queue poisoning via keep-alive socket reuse — CVE-2026-6733

GHSA-35p6-xmwp-9g52 · CWE-367 (TOCTOU race condition)
Fix: ea8930cf fix: guard idle socket validation to skip fresh sockets, hardened by 8e4046e4 keep idle validation on native timers (#5402) and 0fa80869 keep idle validation on global timers (#5409)

An attacker controlling an upstream HTTP/1.1 server could inject unsolicited
responses onto idle keep-alive sockets. On socket reuse, the injected response
was associated with a new request, delivering responses to the wrong requests.

Requirements: attacker-controlled/compromised upstream and active
keep-alive reuse.
Workaround: disable keep-alive reuse with keepAliveTimeout: 0 on the
Client or Pool.

Release contents & deliberate backports

v7.28.0 is a security-only release — every change in it is one of the fixes
above, backported to the v7.x maintenance line on purpose from the v8
development line:

#5423 — backport of the WebSocket maxPayloadSize fragment-count / cumulative-size limits (CVE-2026-12151).
#5402 & #5409 — backport of the idle-validation hardening (native + global timers) for the

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socket-security · 2026-01-19T17:51:47Z

All alerts resolved. Learn more about Socket for GitHub.

This PR previously contained dependency changes with security issues that have been resolved, removed, or ignored.

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socket-security · 2026-05-12T11:11:24Z

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	undici@7.29.0

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chore(deps): update dependency undici to v7.29.0 [security]

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chore(deps): update dependency undici to v7.29.0 [security] - #738

chore(deps): update dependency undici to v7.29.0 [security]#738
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undici Denial of Service attack via bad certificate data

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Undici has an unbounded decompression chain in HTTP responses on Node.js Fetch API via Content-Encoding leads to resource exhaustion

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Undici has an HTTP Request/Response Smuggling issue

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Undici: Malicious WebSocket 64-bit length overflows parser and crashes the client

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Undici has CRLF Injection in undici via upgrade option

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Undici has Unhandled Exception in WebSocket Client Due to Invalid server_max_window_bits Validation

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Undici has Unbounded Memory Consumption in WebSocket permessage-deflate Decompression

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undici vulnerable to cross-user information disclosure via shared cache whitespace bypass

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undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse

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undici WebSocket client vulnerable to denial of service via fragment count bypass

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undici vulnerable to HTTP header injection via Set-Cookie percent-decoding

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renovate Bot commented May 15, 2025 •

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Undici has CRLF Injection in undici via `upgrade` option

`v7.29.0`

`v7.28.0`