CVE-2026-27888Medium▾ Sunlitpypdf: Manipulated FlateDecode XFA streams can exhaust RAM
▾ Sunlit zone — Low / medium · no exploitation signal
impact 27.5 · likelihood 0.1 · 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
Last analysed / modified upstream
0.3%
0.3% → 0.6%
An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the xfa property of a reader or writer and the corresponding stream being compressed using /FlateDecode.
This has been fixed in pypdf==6.7.3.
If projects cannot upgrade yet, consider applying the changes from PR #3658.
pypdf < 6.7.3Upgrade to a patched release:
pypdf 6.7.3Connected by shared product, vendor, weakness, or advisory.
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