Is CVE-2026-22691 actively exploited?

CVE-2026-22691 has no public evidence of in-the-wild exploitation as of 2026-01-22.

What is the CVSS score for CVE-2026-22691?

CVE-2026-22691 has a CVSS score of 2.7 (LOW severity). Vector: 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/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

How do I patch CVE-2026-22691?

Patch guidance is available from pypdf project security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-22691.

Which products are affected by CVE-2026-22691?

1 product: pypdf project pypdf.

CVE-2026-22691 - remediation guidance & executive summary

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.

CVSS Metrics

Vector: 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/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-400 CWE-1333

Metadata

Primary Vendor: PYPDF_PROJECT
Published: 1/10/2026
Last Modified: 1/22/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

pypdf_project : pypdf

Remediation Guidance

Executive Summary

Cite this page

CVE-2026-22691. CVEDatabase.com. Retrieved 1 May 2026. https://cvedatabase.com/cve/CVE-2026-22691

View on NIST NVD

CVE-2026-22691 vulnerability