CVE-2026-27025Medium▾ Sunlitpypdf has possible long runtimes/large memory usage for large /ToUnicode streams
▾ Sunlit zone — Low / medium · no exploitation signal
impact 27.5 · likelihood 0 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 13.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
0.2%
Last analysed / modified upstream
0.2% → 0.2%
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction.
This has been fixed in pypdf==6.7.1.
If you cannot upgrade yet, consider applying the changes from PR #3646.
pypdf < 6.7.1Upgrade to a patched release:
pypdf 6.7.1Connected by shared product, vendor, weakness, or advisory.
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