SB2026042751 - Infinite loop in PyPDF
Published: April 27, 2026
Security Bulletin ID
SB2026042751
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Infinite loop (CVE-ID: CVE-2026-33699)
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an infinite loop in DictionaryObject.read_from_stream when parsing a crafted PDF file in non-strict mode. A remote attacker can supply a specially crafted PDF file to cause a denial of service.
Exploitation requires the application to read the PDF in non-strict mode.
Remediation
Install update from vendor's website.