microsoft · Azure Linux Security Servicing Account (azurelinux-security) · Sep 23, 2026 · Sep 24, 2026
@@ -0,0 +1,288 @@
+From ff37b0c271c865bc5b812f046b210ecfd4008525 Mon Sep 17 00:00:00 2001
+From: AllSpark <allspark@microsoft.com>
+Date: Wed, 23 Sep 2026 05:19:05 +0000
+Subject: [PATCH] Validate Python entry points and sanitize target paths
+
+Signed-off-by: Azure Linux Security Servicing Account <azurelinux-security@microsoft.com>
+Upstream-reference: AI Backport of https://github.com/conda/conda/pull/16168.patch
+---
+ conda/common/path.py            | 34 ++++++++++++++++++++++++++
+ conda/core/path_actions.py      | 14 +++++++++--
+ conda/gateways/disk/create.py   | 13 +++++++++-
+ news/validate-entry-points      | 19 +++++++++++++++
+ tests/common/test_path.py       | 35 +++++++++++++++++++++++++++
+ tests/core/test_path_actions.py | 42 +++++++++++++++++++++++++++++++++
+ 6 files changed, 154 insertions(+), 3 deletions(-)
+ create mode 100644 news/validate-entry-points
+
+diff --git a/conda/common/path.py b/conda/common/path.py
+index a3fea08..e914fb5 100644
+--- a/conda/common/path.py
++++ b/conda/common/path.py
+@@ -3,6 +3,7 @@
+ """Common path utilities."""
+ from __future__ import annotations
+
++import keyword
+ import os
+ import re
+ import subprocess
+@@ -138,6 +139,19 @@ def explode_directories(child_directories: Iterable[tuple[str, ...]]) -> set[str
+     )
+
+
++def is_valid_import_path(path: str) -> bool:
++    """
++    Python import paths are a sequence of non-keyword Python identifiers separated by one period.
++    """
++    # Empty strings are not valid, and return an empty list on split(), making all([]) truthy!
++    if not path:
++        return False
++
++    return all(
++        part.isidentifier() and not keyword.iskeyword(part) for part in path.split(".")
++    )
++
++
+ def pyc_path(py_path, python_major_minor_version):
+     """
+     This must not return backslashes on Windows as that will break
+@@ -171,6 +185,26 @@ def parse_entry_point_def(ep_definition):
+     cmd_mod, func = ep_definition.rsplit(":", 1)
+     command, module = cmd_mod.rsplit("=", 1)
+     command, module, func = command.strip(), module.strip(), func.strip()
++
++    # Validate command
++    if not command or any(c in command for c in ("/", "\\", "\0", "\n", "\r")):
++        raise ValueError(
++            "entry point command must be a simple file name; "
++            f"got invalid characters in {command!r}"
++        )
++    if command.startswith("."):
++        raise ValueError(
++            "entry point command must not be a path-traversal token "
++            f"or hidden name: {command!r}"
++        )
++    # Validate module and func
++    if not is_valid_import_path(module):
++        raise ValueError(
++            f"'{module}' is not a valid absolute import of a Python module"
++        )
++    if not is_valid_import_path(func):
++        raise ValueError(f"'{func}' is not a valid Python function identifier")
++
+     return command, module, func
+
+
+diff --git a/conda/core/path_actions.py b/conda/core/path_actions.py
+index 2b87d0b..acd8caa 100644
+--- a/conda/core/path_actions.py
++++ b/conda/core/path_actions.py
+@@ -1,13 +1,14 @@
+ # Copyright (C) 2012 Anaconda, Inc
+ # SPDX-License-Identifier: BSD-3-Clause
+ """Atomic actions that make up a package installation or removal transaction."""
++import os
+ import re
+ import sys
+ from abc import ABCMeta, abstractmethod, abstractproperty
+ from itertools import chain
+ from json import JSONDecodeError
+ from logging import getLogger
+-from os.path import basename, dirname, getsize, isdir, join
++from os.path import basename, dirname, getsize, isdir, join, normpath
+ from uuid import uuid4
+
+ from .. import CondaError
+@@ -304,6 +305,10 @@ class LinkPathAction(CreateInPrefixPathAction):
+         source_short_path = "Scripts/conda.exe"
+         command, _, _ = parse_entry_point_def(entry_point_def)
+         target_short_path = "Scripts/%s.exe" % command
++        if not normpath(target_short_path).startswith("Scripts" + os.sep):
++            raise ValueError(
++                "target_short_path must point to Scripts/: " + target_short_path
++            )
+         source_path_data = PathDataV1(
+             _path=target_short_path,
+             path_type=PathType.windows_python_entry_point_exe,
+@@ -774,7 +779,12 @@ class CreatePythonEntryPointAction(CreateInPrefixPathAction):
+
+             def this_triplet(entry_point_def):
+                 command, module, func = parse_entry_point_def(entry_point_def)
+-                target_short_path = f"{get_bin_directory_short_path()}/{command}"
++                bin_directory = get_bin_directory_short_path()
++                target_short_path = f"{bin_directory}/{command}"
++                if not normpath(target_short_path).startswith(bin_directory + os.sep):
++                    raise ValueError(
++                        f"target_short_path must point to {bin_directory}: {target_short_path!r}"
++                    )
+                 if on_win:
+                     target_short_path += "-script.py"
+                 return target_short_path, module, func
+diff --git a/conda/gateways/disk/create.py b/conda/gateways/disk/create.py
+index 9aa7002..25b3be2 100644
+--- a/conda/gateways/disk/create.py
++++ b/conda/gateways/disk/create.py
+@@ -16,7 +16,13 @@ from ...auxlib.ish import dals
+ from ...base.constants import CONDA_PACKAGE_EXTENSION_V1, PACKAGE_CACHE_MAGIC_FILE
+ from ...base.context import context
+ from ...common.compat import on_linux, on_win
+-from ...common.path import ensure_pad, expand, win_path_double_escape, win_path_ok
++from ...common.path import (
++    ensure_pad,
++    expand,
++    is_valid_import_path,
++    win_path_double_escape,
++    win_path_ok,
++)
+ from ...common.serialize import json_dump
+ from ...exceptions import BasicClobberError, CondaOSError, maybe_raise
+ from ...models.enums import LinkType
+@@ -116,6 +122,11 @@ def write_as_json_to_file(file_path, obj):
+
+
+ def create_python_entry_point(target_full_path, python_full_path, module, func):
++    if not is_valid_import_path(module):
++        raise ValueError("'module' is not a valid Python import path")
++    if not is_valid_import_path(func):
++        raise ValueError("'func' is not a valid Python import path")
++
+     if lexists(target_full_path):
+         maybe_raise(
+             BasicClobberError(
+diff --git a/news/validate-entry-points b/news/validate-entry-points
+new file mode 100644
+index 0000000..1d1689c
+--- /dev/null
++++ b/news/validate-entry-points
+@@ -0,0 +1,19 @@
++### Enhancements
++
++* <news item>
++
++### Bug fixes
++
++* Validate Python entry point definitions before generating entry point scripts. (#16168)
++
++### Deprecations
++
++* <news item>
++
++### Docs
++
++* <news item>
++
++### Other
++
++* <news item>
+diff --git a/tests/common/test_path.py b/tests/common/test_path.py
+index 61edfb1..c7cd81d 100644
+--- a/tests/common/test_path.py
++++ b/tests/common/test_path.py
+@@ -2,8 +2,11 @@
+ # SPDX-License-Identifier: BSD-3-Clause
+ from logging import getLogger
+
++import pytest
++
+ from conda.common.path import (
+     get_major_minor_version,
++    is_valid_import_path,
+     missing_pyc_files,
+     url_to_path,
+     win_path_backout,
+@@ -168,3 +171,35 @@ def test_get_major_minor_version_no_dot():
+     assert get_major_minor_version("bin/python3.10", False) == "310"
+     assert get_major_minor_version("lib/python310/site-packages/", False) == "310"
+     assert get_major_minor_version("python3", False) is None
++
++
++@pytest.mark.parametrize(
++    "path,result",
++    [
++        ("python", True),
++        ("python.path", True),
++        ("python._path0123", True),
++        # Keywords are forbidden
++        ("import", False),
++        ("import.path", False),
++        # Numbers cannot start the name
++        ("0mod.import", False),
++        # Empty strings or components are not valid
++        ("", False),
++        (".", False),
++        ("..", False),
++        # This also applies to relative imports
++        (".base.common", False),
++        ("..parent.base.common", False),
++        # Some non-ASCII characters are ok!
++        ("ñándú", True),
++        ("ñ.α", True),
++        # Emojis are not
++        ("🚨", False),
++        ("a🚨", False),
++        # Injection prevented
++        ('something"); malicious()', False),
++    ],
++)
++def test_is_valid_import_path(path, result):
++    assert is_valid_import_path(path) is result
+diff --git a/tests/core/test_path_actions.py b/tests/core/test_path_actions.py
+index ecd1ce8..e29bbc4 100644
+--- a/tests/core/test_path_actions.py
++++ b/tests/core/test_path_actions.py
+@@ -1,5 +1,7 @@
+ # Copyright (C) 2012 Anaconda, Inc
+ # SPDX-License-Identifier: BSD-3-Clause
++from __future__ import annotations
++
+ import importlib.util
+ import os
+ import sys
+@@ -293,6 +295,46 @@ def test_CreatePythonEntryPointAction_noarch_python(prefix: Path):
+         assert not isfile(windows_exe_axn.target_full_path)
+
+
++@pytest.mark.parametrize(
++    "definition,result_or_exc",
++    [
++        ("command1=some.module:main", ("command1", "some.module", "main")),
++        (
++            "command1=some.module:SomeClass.method",
++            ("command1", "some.module", "SomeClass.method"),
++        ),
++        (
++            "../bin/python=some.module:main",
++            (ValueError, "simple file name"),
++        ),
++        (
++            "command=.some.module:main",
++            (ValueError, "not a valid absolute import of a Python module"),
++        ),
++        (
++            "command=some..module:main",
++            (ValueError, "not a valid absolute import of a Python module"),
++        ),
++        (
++            "command=some.module:main-function",
++            (ValueError, "not a valid Python function identifier"),
++        ),
++        (
++            "command=some.module:main..function",
++            (ValueError, "not a valid Python function identifier"),
++        ),
++    ],
++)
++def test_entry_point_parse_def(
++    definition: str, result_or_exc: tuple[str, str, str] | tuple[Exception, str]
++):
++    if isinstance(result_or_exc[0], str):
++        assert parse_entry_point_def(definition) == result_or_exc
++    else:
++        with pytest.raises(result_or_exc[0], match=result_or_exc[1]):
++            parse_entry_point_def(definition)
++
++
+ def test_simple_LinkPathAction_hardlink(prefix: Path, pkgs_dir: Path):
+     source_full_path = make_test_file(pkgs_dir)
+     target_short_path = source_short_path = basename(source_full_path)
@@ -1,7 +1,7 @@
 Summary:        Cross-platform, Python-agnostic binary package manager
 Name:           conda
 Version:        24.3.0
-Release:        4%{?dist}
+Release:        5%{?dist}
 License:        BSD-3-Clause AND Apache-2.0
 # The conda code is BSD-3-Clause
 # adapters/ftp.py is Apache-2.0
@@ -20,6 +20,7 @@ Patch3:         conda-cpuinfo.patch
 Patch10004:     0004-Do-not-try-to-run-usr-bin-python.patch
 Patch10005:     0005-Fix-failing-tests-in-test_api.py.patch
 Patch10006:     0006-shell-assume-shell-plugins-are-in-etc.patch
+Patch10007:     CVE-2026-53940.patch
 
 BuildArch:      noarch
 
@@ -402,6 +403,9 @@ PYTHONPATH=%{buildroot}%{python3_sitelib} conda info
 %{_datadir}/conda/condarc.d/
 
 %changelog
+* Wed Sep 23 2026 Azure Linux Security Servicing Account <azurelinux-security@microsoft.com> - 24.3.0-5
+- Patch for CVE-2026-53940
+
 * Thu Aug 07 2025 Riken Maharjan <rmaharjan@microsoft.com> - 24.3.0-4
 - Add missing conda.xsh file to /etc/profile.d
 - also move conda.fish to /etc/fish/conf.d/