CVE-2026-27628 (GCVE-0-2026-27628)
Vulnerability from cvelistv5 – Published: 2026-02-25 02:45 – Updated: 2026-02-27 19:49
VLAI
EPSS
VEX
Title
pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams
Summary
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-25 15:58 UTC
CWE
- CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/py-pdf/pypdf/security/advisori… | x_refsource_CONFIRM |
| https://github.com/py-pdf/pypdf/issues/3654 | x_refsource_MISC |
| https://github.com/py-pdf/pypdf/commit/f0a462d369… | x_refsource_MISC |
Impacted products
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}
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"lastModified": "2026-06-17T10:27:25.050",
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"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
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"modifiedUserInteraction": "NOT_DEFINED",
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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