CVE-2026-27026

EUVD-2026-7787
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used. This vulnerability is fixed in 6.7.1.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.5 MEDIUM
LOCAL
LOW
LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
pypdf_projectpypdf
𝑥
< 6.7.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
pypdf
bookworm
vulnerable
bullseye
postponed
forky
6.9.2-1
fixed
sid
6.9.2-1
fixed
trixie
vulnerable
pypdf2
bookworm
vulnerable
bullseye
vulnerable
trixie
no-dsa
Common Weakness Enumeration
References
https://github.com/py-pdf/pypdf/commit/7905842d833f899f1d3228af7e7467ad80277016
https://github.com/py-pdf/pypdf/pull/3644
https://github.com/py-pdf/pypdf/releases/tag/6.7.1
https://github.com/py-pdf/pypdf/security/advisories/GHSA-9mvc-8737-8j8h