Description
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.
Question to Ask Vendors:
- Can you confirm whether your systems are affected by CVE-2025-40923, and if so, what steps are you currently taking to mitigate this vulnerability?
- What is your estimated timeline for fully resolving CVE-2025-40923 in your products or services, and how will you communicate updates on this issue to us as your customer?
Recommended Actions:
- Check out the advisory links provided below.