Memory Usage Vulnerability in pypdf Library by py-pdf
CVE-2026-28351

6.9MEDIUM

Key Information:

Vendor

Py-PDF

Status
PyPDF
Vendor
CVE Published:
27 February 2026

What is CVE-2026-28351?

The pypdf library, a free and open-source PDF handling tool, contains a vulnerability that allows attackers to create specially crafted PDF files that lead to excessive memory usage during parsing. This issue arises when the content stream is processed with the RunLengthDecode filter, potentially affecting performance and causing denial of service. Users are urged to upgrade to version 6.7.4, where this vulnerability has been addressed, or to implement the proposed changes from the relevant pull request as a temporary solution.

Affected Version(s)

pypdf < 6.7.4

References

https://github.com/py-pdf/pypdf/security/advisories/GHSA-...
x_refsource_CONFIRM
https://github.com/py-pdf/pypdf/pull/3664
x_refsource_MISC
https://github.com/py-pdf/pypdf/commit/f309c6003746414dc7...
x_refsource_MISC

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.