Resource exhaustion in PyPDF - #VU149048
Published: September 12, 2026
Vulnerability identifier: #VU149048
CSH Severity: Medium
CVSS v4: 6.9 [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]
CVE-ID: N/A
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to consume large amounts of memory.
The vulnerability exists due to uncontrolled resource consumption in PyPDF\'s handling of /ToUnicode entries in fonts when parsing unusually large values. A remote attacker can supply a crafted PDF containing unusually large /ToUnicode values to consume large amounts of memory.
This can occur during text extraction.
Affected software
PyPDF
Remediation
Install security update from vendor's website.
PyPDF - update to 6.18.1