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.
History

Sat, 25 Apr 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-770
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Thu, 23 Apr 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 22 Apr 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Py-pdf
Py-pdf pypdf
Vendors & Products Py-pdf
Py-pdf pypdf

Wed, 22 Apr 2026 21:30:00 +0000

Type Values Removed Values Added
Description 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.
Title pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM
Weaknesses CWE-789
References
Metrics cvssV4_0

{'score': 4.8, '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-04-22T21:02:53.156Z

Updated: 2026-04-23T13:45:30.296Z

Reserved: 2026-04-20T14:01:46.671Z

Link: CVE-2026-41312

cve-icon Vulnrichment

Updated: 2026-04-23T13:45:25.607Z

cve-icon NVD

Status : Undergoing Analysis

Published: 2026-04-22T22:16:32.093

Modified: 2026-04-24T14:50:56.203

Link: CVE-2026-41312

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-22T21:02:53Z

Links: CVE-2026-41312 - Bugzilla