CVE-2026-5082

CVE-2026-5082: Amon2::Plugin::Web::CSRFDefender versions from 7.00 through 7.03 for Perl generate an insecure session id

Vendor Tokuhirom
Product Amon2::Plugin::Web::CSRFDefender
Weakness CWE-340
Published April 8, 2026
Last update April 8, 2026

CVSS base score

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 8, 2026 CVE published
April 8, 2026 Record updated