CVE-2026-82398

pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, an attacker can craft a PDF that causes long runtimes when the pypdf/_utils.py function read_until_whitespace reads a stream containing a long run of bytes without whitespace. The function repeatedly performs immutable bytes concatenation in a one-byte loop, causing quadratic processing cost for the long non-whitespace input. This issue is fixed in version 6.15.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/py-pdf/pypdf/commit/4959848e057e37c218dccad7465259210923faaa
https://github.com/py-pdf/pypdf/pull/3947
https://github.com/py-pdf/pypdf/releases/tag/6.15.0
https://github.com/py-pdf/pypdf/security/advisories/GHSA-fc8x-2rww-xw9m

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-31 22:17

Updated : 2026-09-09 16:49

NVD link : CVE-2026-82398

Mitre link : CVE-2026-82398

CVE.ORG link : CVE-2026-82398

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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