CVE-2026-59937
highpriority · track · 30EPSS 0.006 · 50 %ileEUFRUSEPSS · scored 2026-10-28
pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with repeated malformed cross-reference streams that cause pypdf to spend long runtimes recovering broken cross-reference table entries. This issue is fixed in version 6.14.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 2.7–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- GHSA-55h5-xmcq-c37vpypdf: Possible long runtimes for repeated malformed cross-reference entries 2026-07-23ghsa · osvUS
### Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with repeated malformed cross-reference streams. ### Patches This has been fixed in [pypdf==6.14.0](https://github.com/py-pdf/pypdf/releases/tag/6.14.0). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#3887](https://github.com/py-pdf/pypdf/pull/3887).
- CERTFR-2026-AVI-1378Multiples vulnérabilités dans les produits IBMFrançais2026-10-23vendor · certfrFR
- PYSEC-2026-3610pypdf: Possible long runtimes for repeated malformed cross-reference entries 2026-08-04vendor · osvUS
### Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with repeated malformed cross-reference streams. ### Patches This has been fixed in [pypdf==6.14.0](https://github.com/py-pdf/pypdf/releases/tag/6.14.0). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#3887](https://github.com/py-pdf/pypdf/pull/3887).
also known as (6)
Other names and identifiers for this entity.
sources
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references (12)
External citations — patches, advisories, analysis.
- https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50daecnnvd
- https://github.com/py-pdf/pypdf/pull/3887cnnvd
- https://github.com/py-pdf/pypdf/releases/tag/6.14.0cnnvd
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37vcnnvd
- https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50daeenisa_euvd
- https://github.com/py-pdf/pypdf/pull/3887enisa_euvd
- https://github.com/py-pdf/pypdf/releases/tag/6.14.0enisa_euvd
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37venisa_euvd
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