{"id":"CVE-2025-40926","details":"Plack::Middleware::Session::Simple versions before 0.05 for Perl generates session ids insecurely.\n\nThe default session id generator returns a SHA-1 hash seeded with the built-in rand function, the epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage.\n\nPredictable session ids could allow an attacker to gain access to systems.\n\nPlack::Middleware::Session::Simple is intended to be compatible with Plack::Middleware::Session, which had a similar security issue CVE-2025-40923.","modified":"2026-03-14T12:42:41.205272Z","published":"2026-03-05T02:16:39.790Z","references":[{"type":"WEB","url":"https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.05/changes"},{"type":"ADVISORY","url":"https://security.metacpan.org/docs/guides/random-data-for-security.html"},{"type":"ADVISORY","url":"https://www.cve.org/CVERecord?id=CVE-2025-40923"},{"type":"REPORT","url":"https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.04/source/lib/Plack/Middleware/Session/Simple.pm#L43"},{"type":"FIX","url":"https://github.com/kazeburo/Plack-Middleware-Session-Simple/commit/760bb358b8f53e52cf415888a4ac858fd99bb24e.patch"},{"type":"FIX","url":"https://github.com/kazeburo/Plack-Middleware-Session-Simple/pull/4"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/kazeburo/plack-middleware-session-simple","events":[{"introduced":"0"},{"fixed":"f28768ed1d4f3b758bd43f2fd01d26f748b1c88d"},{"fixed":"760bb358b8f53e52cf415888a4ac858fd99bb24e"}],"database_specific":{"versions":[{"introduced":"0"},{"fixed":"0.05"}]}}],"versions":["0.01","0.02","0.03","0.04"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-40926.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}