CVE-2026-27888
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.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
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, https://github.com/py-pdf/pypdf/releases/tag/6.7.3
