Is there a public exploit for CVE-2026-22691?

No public exploit for CVE-2026-22691 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-22691?

CVE-2026-22691 scores CVSS 2.7 (v4.0), rated low. EPSS puts the chance of exploitation in the next 30 days at 0.43%.

What does CVE-2026-22691 affect?

CVE-2026-22691 affects py-pdf pypdf.

2.7 Low

pypdf is a free and open-source pure-python PDF library.

CVE-2026-22691

Impact An attacker who exploits 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. Patches This has been fixed in [pypdf==6.6.0](https://github.com/py-pdf/pypdf/releases/tag/6.6.0). Workarounds python from pypdf import PdfReader, PdfWriter Instead of reader = PdfReader("file.pdf") use the strict mode: reader = PdfReader("file.pdf", strict=True) Instead of writer = PdfWriter(clonefrom="file.pdf") use an explicit strict reader: writer = PdfWriter(clonefrom=PdfReader("file.pdf", strict=True)) Resources This issue has been fixed in #3594.

Assessment

CVSS: 2.7 (v4.0)
Severity: Low
EPSS: 0.43% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 9 January 2026
Last updated: 2 November 2026
Affected: py-pdf · pypdf · pypdf
Weakness: CWE-1333, CWE-400
Assigner: security-advisories@github.com

CVSS vectorCVSS: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

At the source

References

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