CVE-2026-41312 MEDIUM

CVE-2026-41312: pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM

Vendor Py-Pdf
Product pypdf
Weakness CWE-789
Published April 22, 2026
Last update April 23, 2026
View on NVD All CVEs

CVSS base score

4.8/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction —
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

What the vulnerability does

01Description

pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.

Key dates

02Disclosure timeline

April 22, 2026 CVE published
April 23, 2026 Record updated