Vulnerability in Haarg Catalyst::plugin::session

CVE-2025-40924

Catalyst::Plugin::Session before version 0.44 for Perl generates session ids insecurely. The session id is generated from a (usually SHA-1) hash of a simple counter, the epoch time, the built-in rand function, the PID and the current Catalyst context. This information is of low entropy. 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.

EPSS: 0.003 (16.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-40924?
CVE-2025-40924 is a medium-severity vulnerability in Haarg Catalyst::plugin::session, classified under Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). CVSS score: 6.5/10. Published 2025-07-17.
How severe is CVE-2025-40924?
Medium severity. CVSS v3 base score is 6.5 out of 10.