CVE-2026-22691
MEDIUM WAF: Medium
CVSS 5.3
Published: 2026-01-10
CWE-400
pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible long runtimes for malformed startxref. An attacker who uses this vulnerability can craft a PDF which leads to possibly long runtimes for invalid startxref entries. When rebuilding the cross-reference table, PDF files with lots of whitespace characters become problematic. Only the non-strict reading mode is affected. Only the non-strict reading mode is affected. This issue has been patched in version 6.6.0.
WAF Coverage Analysis
Uncontrolled Resource Consumption
Medium WAF Coverage
OWASP: A05:2021 Security Misconfiguration
912xxx - DOS Protection
Affected Software
| Vendor | Product | Version |
|---|---|---|
| pypdf_project | pypdf | up to 6.6.0 |
References
- github.com (Patch)
- github.com (Issue Tracking, Patch)
- github.com (Release Notes)
- github.com (Vendor Advisory, Mitigation)