Description
Amon2::Plugin::Web::CSRFDefender versions from 7.00 through 7.03 for Perl generate an insecure session id. The generate_session_id function will attempt to read bytes from the /dev/urandom device, but if that is unavailable then it generates bytes using SHA-1 hash seeded with the built-in rand() function, the PID, and the high resolution epoch time. 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. Amon2::Plugin::Web::CSRFDefender versions before 7.00 were part of Amon2, which was vulnerable to insecure session ids due to CVE-2025-15604. Note that the author has deprecated this module.
Affected products
tokuhirom: amon2\
References3
- metacpan.org/release/TOKUHIROM/Amon2-Plugin-Web-CSRFDefender-7.… Product
- metacpan.org/release/TOKUHIROM/Amon2-Plugin-Web-CSRFDefender-7.… Release Notes
- www.cve.org/CVERecord?id=CVE-2025-15604 Third Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 37 · as of 12 November 2026
- CWE
- CWE-338CWE-340
Could this be exploited in your environment?
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