diff --git a/packages/syft-job/src/syft_job/job_repr.py b/packages/syft-job/src/syft_job/job_repr.py
index accd0e90eeb..d6787e7e9fb 100644
--- a/packages/syft-job/src/syft_job/job_repr.py
+++ b/packages/syft-job/src/syft_job/job_repr.py
@@ -121,12 +121,17 @@ def _repr_html_(self) -> str:
             </div>
             """
 
-        html_content = self._convert_ansi_to_html(raw_content)
-        html_content = (
-            html_content.replace("&", "&amp;")
-            .replace('"', "&quot;")
-            .replace("'", "&#x27;")
-        )
+        # Fix 1: HTML-escape the raw text *first* so that characters like
+        # `<`, `>`, `&` and `'` in the job's own output cannot be
+        # interpreted as HTML markup.  `quote=False` keeps `\""` as `\""`
+        # rather than `&quot;` -- the ANSI->HTML step that follows will insert
+        # double-quoted `style` attributes that must remain unescaped.
+        escaped_content = escape(raw_content, quote=False)
+
+        # Fix 2: Convert ANSI codes to HTML spans *after* escaping, so the
+        # span tags we emit are real markup.  The style attributes use plain
+        # double-quotes that were preserved by `quote=False` above.
+        html_content = self._convert_ansi_to_html(escaped_content)
 
         clean_content = self._strip_ansi_codes(raw_content)
         lines = clean_content.split("\n")
diff --git a/packages/syft-job/src/syft_job/job_stdout.py b/packages/syft-job/src/syft_job/job_stdout.py
index 64ca7bffbf8..6565665d92d 100644
--- a/packages/syft-job/src/syft_job/job_stdout.py
+++ b/packages/syft-job/src/syft_job/job_stdout.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import re
+from html import escape
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
@@ -20,7 +21,14 @@ def _strip_ansi_codes(self, text: str) -> str:
         return ansi_escape.sub("", text)
 
     def _convert_ansi_to_html(self, text: str) -> str:
-        """Convert ANSI color codes to HTML spans."""
+        """Convert ANSI color codes to HTML spans.
+
+        The *text* argument must already be HTML-escaped (``<``, ``>``, ``&``
+        and ``'`` replaced with entity references, ``"`` kept as-is via
+        ``quote=False``) so that only the ANSI escape sequences remain
+        unprocessed.  The ``<span>`` tags emitted here use plain double-quoted
+        ``style`` attributes that must never be entity-escaped afterwards.
+        """
         # Basic ANSI color code mapping
         ansi_colors = {
             "30": "color: #000000;",  # black
@@ -129,17 +137,17 @@ def _repr_html_(self) -> str:
             </div>
             """
 
-        # Convert ANSI codes to HTML for display
-        html_content = self._convert_ansi_to_html(raw_content)
-
-        # Escape any remaining HTML characters that aren't our color spans
-        # We need to be careful not to escape our intentional HTML
-        html_content = (
-            html_content.replace("&", "&amp;")
-            .replace('"', "&quot;")
-            .replace("'", "&#x27;")
-        )
-        # Don't escape < and > since we want our HTML spans to work
+        # Fix 1: HTML-escape the raw text *first* so that characters like
+        # `<`, `>`, `&` and `'` in the job's own output cannot be
+        # interpreted as HTML markup.  `quote=False` keeps `\""` as `\""`
+        # rather than `&quot;` -- the ANSI->HTML step that follows will insert
+        # double-quoted `style` attributes that must remain unescaped.
+        escaped_content = escape(raw_content, quote=False)
+
+        # Fix 2: Convert ANSI codes to HTML spans *after* escaping, so the
+        # span tags we emit are real markup.  The style attributes use plain
+        # double-quotes that were preserved by `quote=False` above.
+        html_content = self._convert_ansi_to_html(escaped_content)
 
         # Count lines and characters (use clean content for stats)
         clean_content = self._strip_ansi_codes(raw_content)
diff --git a/packages/syft-job/tests/test_issue_9586_html_viewer.py b/packages/syft-job/tests/test_issue_9586_html_viewer.py
new file mode 100644
index 00000000000..fa627e47ace
--- /dev/null
+++ b/packages/syft-job/tests/test_issue_9586_html_viewer.py
@@ -0,0 +1,233 @@
+"""Tests for issue #9586: job stdout/stderr HTML views drop `<...>` text and show no ANSI colors.
+
+Two bugs were present in StdoutViewer._repr_html_ (job_stdout.py) and
+StderrViewer._repr_html_ (job_repr.py):
+
+  Bug 1 – Wrong escaping order: ANSI codes were converted to
+           ``<span style="color: #cd3131;">`` first, and then ``"`` was
+           replaced with ``&quot;``.  Every resulting span became
+           ``<span style=&quot;color: #cd3131;&quot;>``, so the browser
+           ignored the style and colored output showed up without colours.
+
+  Bug 2 – Missing HTML escaping: ``<`` and ``>`` were never escaped.
+           Any output text that looks like an HTML tag (e.g.
+           ``<class 'int'>`` or tracebacks containing ``in <module>``)
+           was parsed as HTML and disappeared from the view.  Worse,
+           output containing ``<script>`` could inject arbitrary markup.
+
+The fix is to escape ``<``, ``>``, ``&`` and ``'`` *before* converting
+ANSI sequences to ``<span>`` tags, using ``html.escape(text, quote=False)``
+(``quote=False`` preserves ``"`` so the span ``style`` attributes remain
+valid HTML attribute values).
+"""
+from __future__ import annotations
+
+from pathlib import Path
+from types import SimpleNamespace
+
+
+# ---------------------------------------------------------------------------
+# Helpers – build minimal stand-ins for JobInfo so we can unit-test the
+# viewers without any real syft-job infrastructure.
+# ---------------------------------------------------------------------------
+
+
+def _make_stdout_viewer(tmp_path: Path, content: str):
+    """Return a StdoutViewer whose job_info points at *content* as stdout."""
+    from syft_job.job_stdout import StdoutViewer  # type: ignore[import]
+
+    job_dir = tmp_path / "job"
+    job_dir.mkdir(exist_ok=True)
+    (job_dir / "stdout.txt").write_text(content, encoding="utf-8")
+    job_info = SimpleNamespace(
+        status="done",
+        artifact_path=lambda name: job_dir / name,
+    )
+    return StdoutViewer(job_info)
+
+
+def _make_stderr_viewer(tmp_path: Path, content: str):
+    """Return a StderrViewer whose job_info points at *content* as stderr."""
+    from syft_job.job_repr import StderrViewer  # type: ignore[import]
+
+    job_dir = tmp_path / "job"
+    job_dir.mkdir(exist_ok=True)
+    (job_dir / "stderr.txt").write_text(content, encoding="utf-8")
+    job_info = SimpleNamespace(
+        status="done",
+        artifact_path=lambda name: job_dir / name,
+    )
+    return StderrViewer(job_info)
+
+
+# ---------------------------------------------------------------------------
+# Bug 2 – HTML injection / disappearing angle-bracket text (StdoutViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stdout_html_escapes_angle_brackets(tmp_path: Path) -> None:
+    """``<class 'int'>`` must appear as ``&lt;class &#x27;int&#x27;&gt;``."""
+    viewer = _make_stdout_viewer(tmp_path, "<class 'int'>\n")
+    html = viewer._repr_html_()
+
+    # The literal angle-bracket text must not appear unescaped in the output.
+    assert "<class" not in html, "unescaped '<class' found – tag would be swallowed"
+    # It must appear as properly escaped entities instead.
+    assert "&lt;class" in html or "&#x3C;" in html.lower()
+
+
+def test_stdout_html_escapes_traceback_module_tag(tmp_path: Path) -> None:
+    """``in <module>`` from tracebacks must survive HTML rendering."""
+    viewer = _make_stdout_viewer(tmp_path, "Traceback:\n  in <module>\n")
+    html = viewer._repr_html_()
+
+    assert "<module>" not in html, "unescaped '<module>' leaks into HTML"
+    assert "&lt;module&gt;" in html
+
+
+def test_stdout_html_escapes_script_injection(tmp_path: Path) -> None:
+    """Malicious ``<script>`` in job output must not reach the browser."""
+    payload = "<script>alert('xss')</script>"
+    viewer = _make_stdout_viewer(tmp_path, payload)
+    html = viewer._repr_html_()
+
+    assert "<script>" not in html, "XSS script tag escaped into HTML output"
+
+
+# ---------------------------------------------------------------------------
+# Bug 1 – ANSI colour codes produce broken ``style=&quot;...&quot;`` spans (StdoutViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stdout_html_ansi_red_produces_valid_style_attribute(tmp_path: Path) -> None:
+    """Red ANSI text must produce a ``style="color: #cd3131;"`` span."""
+    viewer = _make_stdout_viewer(tmp_path, "\x1b[31mfailed\x1b[0m\n")
+    html = viewer._repr_html_()
+
+    # The double-quote must NOT be entity-escaped in the style attribute.
+    assert 'style="color: #cd3131;"' in html, (
+        "ANSI red colour span has broken style attribute; "
+        "got: " + html[html.find("span") - 5 : html.find("span") + 80]
+    )
+    assert "style=&quot;" not in html, "style attribute double-quotes were entity-escaped"
+
+
+def test_stdout_html_ansi_bold_produces_valid_style_attribute(tmp_path: Path) -> None:
+    """Bold ANSI text must produce a ``style="font-weight: bold;"`` span."""
+    viewer = _make_stdout_viewer(tmp_path, "\x1b[1mbold text\x1b[0m\n")
+    html = viewer._repr_html_()
+
+    assert 'style="font-weight: bold;"' in html
+    assert "style=&quot;" not in html
+
+
+# ---------------------------------------------------------------------------
+# Both bugs together (StdoutViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stdout_html_ansi_color_and_angle_brackets_combined(tmp_path: Path) -> None:
+    """Coloured output that also contains ``<...>`` text must render correctly."""
+    content = "\x1b[31m<class 'int'>\x1b[0m\n"
+    viewer = _make_stdout_viewer(tmp_path, content)
+    html = viewer._repr_html_()
+
+    # No unescaped angle bracket from the class repr.
+    assert "<class" not in html
+    assert "&lt;class" in html or "&#x3C;" in html.lower()
+    # Style attribute must use real double-quotes, not entity-escaped ones.
+    assert 'style="color: #cd3131;"' in html
+    assert "style=&quot;" not in html
+
+
+# ---------------------------------------------------------------------------
+# Bug 2 – HTML injection / disappearing angle-bracket text (StderrViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stderr_html_escapes_angle_brackets(tmp_path: Path) -> None:
+    """``<class 'int'>`` on stderr must appear as escaped entities."""
+    viewer = _make_stderr_viewer(tmp_path, "<class 'int'>\n")
+    html = viewer._repr_html_()
+
+    assert "<class" not in html, "unescaped '<class' found – tag would be swallowed"
+    assert "&lt;class" in html or "&#x3C;" in html.lower()
+
+
+def test_stderr_html_escapes_traceback_module_tag(tmp_path: Path) -> None:
+    """``in <module>`` from tracebacks must survive HTML rendering on stderr."""
+    viewer = _make_stderr_viewer(tmp_path, "Traceback:\n  in <module>\n")
+    html = viewer._repr_html_()
+
+    assert "<module>" not in html
+    assert "&lt;module&gt;" in html
+
+
+def test_stderr_html_escapes_script_injection(tmp_path: Path) -> None:
+    """Malicious ``<script>`` in stderr output must not reach the browser."""
+    payload = "<script>alert('xss')</script>"
+    viewer = _make_stderr_viewer(tmp_path, payload)
+    html = viewer._repr_html_()
+
+    assert "<script>" not in html
+
+
+# ---------------------------------------------------------------------------
+# Bug 1 – ANSI colour codes produce broken spans (StderrViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stderr_html_ansi_red_produces_valid_style_attribute(tmp_path: Path) -> None:
+    """Red ANSI text on stderr must produce a valid ``style="..."`` span."""
+    viewer = _make_stderr_viewer(tmp_path, "\x1b[31merror message\x1b[0m\n")
+    html = viewer._repr_html_()
+
+    assert 'style="color: #cd3131;"' in html
+    assert "style=&quot;" not in html
+
+
+def test_stderr_html_ansi_bold_produces_valid_style_attribute(tmp_path: Path) -> None:
+    """Bold ANSI text on stderr must produce a valid ``style="..."`` span."""
+    viewer = _make_stderr_viewer(tmp_path, "\x1b[1mWARNING\x1b[0m\n")
+    html = viewer._repr_html_()
+
+    assert 'style="font-weight: bold;"' in html
+    assert "style=&quot;" not in html
+
+
+# ---------------------------------------------------------------------------
+# Both bugs together (StderrViewer)
+# ---------------------------------------------------------------------------
+
+
+def test_stderr_html_ansi_color_and_angle_brackets_combined(tmp_path: Path) -> None:
+    """Coloured stderr output with ``<...>`` text must render correctly."""
+    content = "\x1b[31m<class 'int'>\x1b[0m\n"
+    viewer = _make_stderr_viewer(tmp_path, content)
+    html = viewer._repr_html_()
+
+    assert "<class" not in html
+    assert "&lt;class" in html or "&#x3C;" in html.lower()
+    assert 'style="color: #cd3131;"' in html
+    assert "style=&quot;" not in html
+
+
+# ---------------------------------------------------------------------------
+# Regression – plain text (no ANSI, no special chars) is still displayed
+# ---------------------------------------------------------------------------
+
+
+def test_stdout_html_plain_text_is_displayed(tmp_path: Path) -> None:
+    """Plain output without ANSI codes must still appear in the HTML."""
+    viewer = _make_stdout_viewer(tmp_path, "hello from job\n")
+    html = viewer._repr_html_()
+
+    assert "hello from job" in html
+
+
+def test_stderr_html_plain_text_is_displayed(tmp_path: Path) -> None:
+    """Plain stderr output without ANSI codes must still appear in the HTML."""
+    viewer = _make_stderr_viewer(tmp_path, "some warning\n")
+    html = viewer._repr_html_()
+
+    assert "some warning" in html