CVEvulnerability
CVE-2025-40923
7.3 HIGH
Official page ↗
- Status
- Deferred
- Published
- 2025-07-16
- Last modified
- 2026-06-17
- Assigner
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
- CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
- 7.3 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- Weaknesses
- CWE-338, CWE-340
Description
Plack-Middleware-Session before version 0.35 for Perl generates session ids insecurely.
The 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.
Predicable session ids could allow an attacker to gain access to systems.
Related
References
- https://github.com/plack/Plack-Middleware-Session/commit/1fbfbb355e34e7f4b3906f66cf958cedadd2b9be.patch github.com
- https://github.com/plack/Plack-Middleware-Session/pull/52 github.com
- https://metacpan.org/release/MIYAGAWA/Plack-Middleware-Session-0.34/source/lib/Plack/Session/State.pm#L22 metacpan.org
- https://security.metacpan.org/docs/guides/random-data-for-security.html security.metacpan.org
- http://www.openwall.com/lists/oss-security/2025/07/16/4 www.openwall.com