CVE-2025-40923CWE-338CWE-340

Plack-Middleware-Session before version 0.35 for Perl generates session ids insecurely

High · published July 16, 2025

CVSS v3.1
7.3
EPSS
0%
Percentile
31.9
In the wild
Unconfirmed
What it is

Plack-Middleware-Session before version 0.35 for Perl generates session ids insecurely.

The default session id generator returns a SHA-1 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.

The record
Technical detail
CVSS v3.1
7.3 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00390 · 31.9th percentile
Weaknesses
CWE-338 · Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG); CWE-340 · Generation of Predictable Numbers or Identifiers
Published
2025-07-16T13:05Z
EPSS history
Timeline
  • 16 JUL 13:05Z
    Plack-Middleware-Session before version 0.35 for Perl generates session ids insecurely
    cvelistv5