py-pdf/pypdf · Security
pypdf: Possible long runtimes for partially malformed FlateDecode streams (Follow-up)
- GHSA ID
- GHSA-jw7q-gvrg-4vj3
- CVE ID
- CVE-2026-102997
- Severity
- high
- Published
- Updated
- CVSS v4
- 8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Description
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a partially malformed /FlateDecode stream, where the byte-by-byte decompression is used.
Patches
This has been fixed in pypdf==6.18.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4073.
CWEs
- CWE-400 · Uncontrolled Resource Consumption
- CWE-407 · Inefficient Algorithmic Complexity
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-jw7q-gvrg-4vj3 ↗
- https://nvd.nist.gov/vuln/detail/CVE-2026-102997 ↗
- https://github.com/py-pdf/pypdf/pull/4073 ↗
- https://github.com/py-pdf/pypdf/commit/d9d38cf99b115deb562d3b68f36c33027bc04f79 ↗
- https://github.com/py-pdf/pypdf/releases/tag/6.18.1 ↗
- https://github.com/advisories/GHSA-jw7q-gvrg-4vj3 ↗