Riskcovery

CVE-2026-22691

pypdf has possible long runtimes for malformed startxref

State
Published
Severity
2.7 Low
Published
Jan 10, 2026
Updated
Jan 12, 2026
Reserved
Jan 8, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
4.02.7 LowCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:UGitHub_M

Weaknesses

  • CWE-1333 Inefficient Regular Expression Complexity
  • CWE-400 Uncontrolled Resource Consumption

Affected Products

ProductVersions
pypdfpy-pdf
  • < 6.6.0Affected

References

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