CVE-2026-57204 MEDIUM

CVE-2026-57204: pypdf: Missing stream length values ignore defined limits

Vendor Py-Pdf
Product pypdf
Weakness CWE-400
Published June 30, 2026
Last update July 1, 2026
View on NVD All CVEs

CVSS base score

6.9/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/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. 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.

Key dates

02Disclosure timeline

June 30, 2026 CVE published
July 1, 2026 Record updated