CVE-2026-27026 — pypdf possibly has long runtimes for malformed FlateDecode streams
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a ma…
Published: 2026-02-20 · CVSS: 6.9 · CVSS 4.0
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used. This vulnerability is fixed in 6.7.1.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7