py-pdf/pypdf · Security
pypdf: Manipulated FlateDecode XFA streams can exhaust RAM
- GHSA ID
- GHSA-x7hp-r3qg-r3cj
- CVE ID
- CVE-2026-27888
- Severity
- medium
- Published
- Updated
- CVSS v4
- 6.6 · 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/E:U
Description
Impact
An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the xfa property of a reader or writer and the corresponding stream being compressed using /FlateDecode.
Patches
This has been fixed in pypdf==6.7.3.
Workarounds
If projects cannot upgrade yet, consider applying the changes from PR #3658.
CWEs
- CWE-400 · Uncontrolled Resource Consumption
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-x7hp-r3qg-r3cj ↗
- https://nvd.nist.gov/vuln/detail/CVE-2026-27888 ↗
- https://github.com/py-pdf/pypdf/pull/3658 ↗
- https://github.com/py-pdf/pypdf/commit/7a4c8246ed48d9d328fb596942271da47b6d109c ↗
- https://github.com/py-pdf/pypdf/releases/tag/6.7.3 ↗
- https://github.com/advisories/GHSA-x7hp-r3qg-r3cj ↗