CVE-2025-40931

Critical

Description

Apache::Session::Generate::MD5 versions through 1.94 for Perl create insecure session id. Apache::Session::Generate::MD5 generates session ids insecurely. The default session id generator returns a MD5 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. Note that the libapache-session-perl package in some Debian-based Linux distributions may be patched to use Crypt::URandom.

SeverityCritical
CVSS9.1
Exploit probability—
ProductChorny Apache\
PublishedMar 5, 2026
First seenMar 5, 2026

How to fix

Affected products

ProductAffected versionsFixed in
chorny apache\\ ≤ v ≤ 1.94—

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