PYSEC-2026-3014

vendorUSosv

pypdf vulnerable to inefficient decoding of ASCIIHexDecode streams

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

### Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the `/ASCIIHexDecode` filter. ### Patches This has been fixed in [pypdf==6.7.5](https://github.com/py-pdf/pypdf/releases/tag/6.7.5). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#3666](https://github.com/py-pdf/pypdf/pull/3666).

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describes (1)

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CVE-2026-28804USmedium5.3—
pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires…
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references

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