CVE-2026-48156

LOW

pypdf: Possible long runtimes for zero-only width values in cross-reference streams

Title source: cna
STIX 2.1

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.12.0, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values. This vulnerability is fixed in 6.12.0.

References (3)

Core 3
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/pull/3791
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/releases/tag/6.12.0

Scores

CVSS v3 3.3
EPSS 0.0012
EPSS Percentile 2.4%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-834
Status published
Products (3)
py-pdf/pypdf < 6.12.0
pypdf_project/pypdf < 6.12.0
pypi/pypdf 0 - 6.12.0PyPI
Published May 28, 2026
Tracked Since May 28, 2026