pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.4, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream using the RunLengthDecode filter. This has been fixed in pypdf 6.7.4. As a workaround, consider applying the changes from PR #3664.
https://github.com/py-pdf/pypdf/security/advisories/GHSA-f2v5-7jq9-h8cg
https://github.com/py-pdf/pypdf/releases/tag/6.7.4
https://github.com/py-pdf/pypdf/pull/3664
https://github.com/py-pdf/pypdf/commit/f309c6003746414dc7b5048c19e6d879ff2dc858
Published: 2026-02-27
Updated: 2026-03-03
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00049