PDM Trojan Lockfile

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.8 · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

• CVE-2023-45805: 0.45% estimated exploitation activity in the next 30 days; percentile 39.29 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary It's possible to craft a malicious pdm.lock file that could allow e.g. an insider or a malicious open source project to appear to depend on a trusted PyPI project, but actually install another project. Details Project foo can be targeted by creating the project foo-2 and uploading the file foo-2-2.tar.gz to pypi.org. PyPI will see this as project foo-2 version 2, while PDM will see this as project foo version 2-2. The version must only be parseable as a version (and the filename must be a prefix of the project name), but it's not verified to match the version being installed. (Version 2-2 is also not a valid normalized version per PEP 440.) Matching the project name exactly (not just prefix) would fix the issue. The version should also be verified to avoid version downgrade attacks. PoC Example pdm.lock snippet to appear to depend on foo but actually install foo-2 Impact When installing dependencies with PDM, what's actually installed could differ from what's listed in…

Published by the source

20 Oct 2023, 19:30 UTC

Last modified by the source

7 Jul 2026, 17:56 UTC

Source last checked

26 Oct 2026, 13:12 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-j44v-mmf2-xvm9

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-j44v-mmf2-xvm9

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2023-45805

Advisory: PDM Trojan Lockfile
IDs: CVE-2023-45805, GHSA-j44v-mmf2-xvm9
Record: https://patchnext.com/advisories/cve-2023-45805 (revision 2, source checked 26 Oct 2026, 13:12 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI pdm: affected <= 2.9.3

## Suggested inspection (read-only)
- `python -m pip show pdm`: prints the installed version. Run with the environment that serves production active.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on pdm.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-j44v-mmf2-xvm9 (OSV record GHSA-j44v-mmf2-xvm9 lists affected ranges: PyPI pdm >=0 <=2.9.3)
- Verified: https://github.com/advisories/GHSA-j44v-mmf2-xvm9 (GitHub-reviewed advisory GHSA-j44v-mmf2-xvm9 lists affected ranges: PyPI pdm >=0 <=2.9.3)

Commands are suggestions: review each one before running it.