Fluid Attacks Database

Description

pypdf: Possible long runtimes when generating appearance streams

Impact

An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires updating form field values with flattening enabled, which triggers appearance stream generation.

Patches

This has been fixed in pypdf==6.19.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #4087.

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Component	Affected version	Patched versions
pypi	pypdf	>=0 <6.19.0	6.19.0
debian 13	pypdf	=5.4.0-1 \|\| =6.19.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 12	pypdf	=3.17.4-1 \|\| =3.4.1-1 \|\| =3.4.1-1+deb12u1 \|\| =4.0.0-1 \|\| =4.0.0-1~exp1 \|\| =4.0.1-1 \|\| =4.0.2-1 \|\| =4.1.0-1 \|\| =4.2.0-1 \|\| =4.3.1-1 \|\| =5.4.0-1 \|\| =6.19.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 14	pypdf	=5.4.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2 \|\| >=0 <6.19.0-1	6.19.0-1

Aliases

1. CVE-2026-1029982. NVD-2026-1029983. OSV-2026-1029984. OSV-DEBIAN-2026-1029985. GHSA-php9-fj8v-98fj6. GCVE-2026-1029987. SECURITY-TRACKER-CVE-2026-102998

References

1. https://github.com/py-pdf/pypdf/security/advisories/GHSA-php9-fj8v-98fj2. https://github.com/py-pdf/pypdf/pull/40873. https://github.com/py-pdf/pypdf/commit/959467a9b95be83e2dc5ae873ece5f371263ede74. https://github.com/py-pdf/pypdf/releases/tag/6.19.0

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