CVE-2026-22691 (GCVE-0-2026-22691)

Vulnerability from cvelistv5 – Published: 2026-01-10 04:46 – Updated: 2026-01-10 04:46
VLAI?
Title
pypdf has possible long runtimes for malformed startxref
Summary
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.
Severity ?
2.7 (Low)
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
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version
py-pdf pypdf Affected: < 6.6.0
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      "source": {
        "advisory": "GHSA-4f6g-68pf-7vhv",
        "discovery": "UNKNOWN"
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      "title": "pypdf has possible long runtimes for malformed startxref"
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    "dateReserved": "2026-01-08T19:23:09.855Z",
    "dateUpdated": "2026-01-10T04:46:12.423Z",
    "state": "PUBLISHED"
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  }
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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