CVE-2026-71870

Summary

pypdf: Possible large memory usage for large /ToUnicode streams

Severity

medium

EPSS

0.1% (p2)

CWE

CWE-400

Also known as

GHSA-fp3f-mc75-235c

Published

2026-08-07

Updated

2026-08-09

Advisory details

Impact

An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction.

Patches

This has been fixed in pypdf==6.15.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #3944.

References

• https://github.com/advisories/GHSA-fp3f-mc75-235c
• https://github.com/py-pdf/pypdf/security/advisories/GHSA-fp3f-mc75-235c
• https://github.com/py-pdf/pypdf/pull/3944
• https://github.com/py-pdf/pypdf/commit/afba8080e19d29a3c256a742b340995e695b35aa
• https://github.com/py-pdf/pypdf/releases/tag/6.15.0

Related advisories

• CVE-2026-115572 — high · PyPI/pypdf
• CVE-2026-115585 — high · PyPI/pypdf
• CVE-2026-102999 — high · PyPI/pypdf
• CVE-2026-102998 — high · PyPI/pypdf
• CVE-2026-103000 — high · PyPI/pypdf
• CVE-2026-102997 — high · PyPI/pypdf
• CVE-2026-102996 — high · PyPI/pypdf
• CVE-2026-102995 — high · PyPI/pypdf

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