Summary
pypdf: Inefficient handling of non-whitespace inputs in read_until_whitespace
Advisory details
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a call to read_until_whitespace with an input which does not have whitespace for a long time.
Patches
This has been fixed in pypdf==6.15.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3947.
References
- https://github.com/advisories/GHSA-fc8x-2rww-xw9m
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-fc8x-2rww-xw9m
- https://nvd.nist.gov/vuln/detail/CVE-2026-82398
- https://github.com/py-pdf/pypdf/pull/3947
- https://github.com/py-pdf/pypdf/commit/4959848e057e37c218dccad7465259210923faaa
- https://github.com/py-pdf/pypdf/releases/tag/6.15.0
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