VULNERABILITY INTELLIGENCE

CVE-2025-40931

CVSS score9.1 CRITICAL
EPSS probability0.64%
CISA KEVNot currently listed
Published2026-03-05
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

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.

Weakness classification

  • CWE-338: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
  • CWE-340: Generation of Predictable Numbers or Identifiers

Primary references