Input validation error in PyPDF - CVE-2026-113786
Published: October 21, 2026 / Updated: October 23, 2026
Vulnerability identifier: #VU156653
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-113786
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause unintended image parsers to be invoked when a crafted PDF is processed.
The vulnerability exists due to improper input validation in pypdf image loading when loading image data that claims to use the /DCTDecode filter for JPEG data. A remote attacker can craft a PDF containing such image data to cause arbitrary image parsers to be called.
Affected software
PyPDF
How to mitigate CVE-2026-113786
Install security update from vendor's website.
PyPDF - update to 6.21.1