CVE-2026-57204

MEDIUM

pypdf: Missing stream length values ignore defined limits

Title source: cna
STIX 2.1

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.13.3, a maliciously crafted PDF can cause DoS. An attacker who uses this vulnerability can craft a PDF which leads to large memory usage, as MAX_DECLARED_STREAM_LENGTH is sometimes ignored. This requires parsing a content stream without a /Length value. This issue has been fixed in version 6.13.3.

References (2)

Core 2
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/py-pdf/pypdf/releases/tag/6.13.3

Scores

CVSS v3 6.5
EPSS 0.0021
EPSS Percentile 10.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-400
Status published
Products (2)
py-pdf/pypdf < 6.13.3
pypdf_project/pypdf < 6.13.3
Published Jun 30, 2026
Tracked Since Jul 01, 2026