PYSEC-2026-3018

vendorUSosv

pypdf: Possible infinite loop when processing threads/articles in writer

view advisory published 2026-07-13Licence: CC-BY-4.0

### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with threads/articles into a writer. ### Patches This has been fixed in [pypdf==6.13.1](https://github.com/py-pdf/pypdf/releases/tag/6.13.1). ### Workarounds If users cannot upgrade yet, consider applying the changes from PR [#3839](https://github.com/py-pdf/pypdf/pull/3839).

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describes (1)

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