XML Entity Expansion in PyPDF - CVE-2026-40260
Published: April 10, 2026
Vulnerability identifier: #VU125811
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-40260
CWE-ID: CWE-776
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause excessive memory consumption.
The vulnerability exists due to improper restriction of recursive entity references in DTDs in the XMP metadata parser when parsing XMP metadata from a PDF file. A remote attacker can supply a specially crafted PDF to cause excessive memory consumption.
Exploitation requires the application to parse the XMP metadata.
Affected software
PyPDF
How to mitigate CVE-2026-40260
Install security update from vendor's website.
PyPDF - update to 6.10.0