# Picklescan is vulnerable to RCE through missing detection when calling numpy.f2py.crackfortran.\_eval_length

Advisory record · `GHSA-6556-fwc2-fg2p`

- **Identifiers:** `GHSA-6556-fwc2-fg2p` · `CVE-2025-71339` · `PYSEC-2026-1783`
- **State:** Confirmed
- **Severity:** CVSS 7.6 High
- **Critical:** No
- **Weakness (CWE):** [CWE-94](https://cwe.mitre.org/data/definitions/94.html) · [CWE-502](https://cwe.mitre.org/data/definitions/502.html)
- **Tags:** [Code injection](https://agentprime.io/advisories/tag/code-injection.md) · [Insecure deserialization](https://agentprime.io/advisories/tag/deserialization.md)
- **Published:** 30 Dec 2025
- **Updated:** 18 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 30 Dec 2025, 15:20 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `picklescan` (PyPI): affected `<0.0.33`; fixed in `0.0.33`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Picklescan versions before 0.0.33 fail to flag pickles that call numpy.f2py.crackfortran.\_eval_length, so a malicious pickle can pass the scan as safe. If a victim loads such a file with pickle.load(), an attacker can run arbitrary code on their machine. Upgrade picklescan to version 0.0.33 or later.

Written 5 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 7.6 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`, from CNA (VulnCheck)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0038, the 32nd percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:42 UTC: First seen by agentprime
- 31 Oct 2026, 14:42 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-6556-fwc2-fg2p)

## Sources

- [GitHub Advisory Database: GHSA-6556-fwc2-fg2p](https://github.com/advisories/GHSA-6556-fwc2-fg2p)
- [OSV: GHSA-6556-fwc2-fg2p](https://osv.dev/vulnerability/GHSA-6556-fwc2-fg2p)
- <https://github.com/mmaitre314/picklescan/security/advisories/GHSA-6556-fwc2-fg2p>
- <https://nvd.nist.gov/vuln/detail/CVE-2025-71339>
- <https://github.com/mmaitre314/picklescan/pull/53>
- <https://github.com/mmaitre314/picklescan/commit/70c1c6c31beb6baaf52c8db1b6c3c0e84a6f9dab>
- <https://github.com/advisories/GHSA-6556-fwc2-fg2p>
- <https://github.com/mmaitre314/picklescan>
- <https://github.com/mmaitre314/picklescan/releases/tag/v0.0.33>
- <https://github.com/pypa/advisory-database/tree/main/vulns/picklescan/PYSEC-2026-1783.yaml>
- <https://pypi.org/project/picklescan>
- <https://www.vulncheck.com/advisories/picklescan-arbitrary-code-execution-via-numpy-f2py-crackfortran-eval-length-gadget>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-6556-fwc2-fg2p>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-6556-fwc2-fg2p/>. Everything for agents: <https://agentprime.io/llms.txt>.