pypdf: Possible long runtimes/large memory usage for large CID font width ranges
### Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires parsing the font width entries of a font with unusually large values, for example during text extraction. ### Patches This has been fixed in [pypdf==6.15.0](https://github.com/py-pdf/pypdf/releases/tag/6.15.0). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#3946](https://github.com/py-pdf/pypdf/pull/3946).
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-71852US | low3.3 | — | ||
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause long runtimes and large memory consumption when pypdf/_font.py function Font._coll… | ||||
references
External citations — patches, advisories, analysis.
- https://github.com/advisories/GHSA-fwg2-594c-jp42ADVISORY
- https://github.com/py-pdf/pypdfPACKAGE
- https://github.com/py-pdf/pypdf/commit/51cb6acf9e8a35b77e90b4d87d28fe3e1416d7d7WEB
- https://github.com/py-pdf/pypdf/pull/3946WEB
- https://github.com/py-pdf/pypdf/releases/tag/6.15.0WEB
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-fwg2-594c-jp42WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-71852ADVISORY
- https://pypi.org/project/pypdfPACKAGE
Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.
Free scan