CVE-2025-40926 (GCVE-0-2025-40926)
Vulnerability from cvelistv5 – Published: 2026-03-05 01:24 – Updated: 2026-03-05 16:29
VLAI?
Title
Plack::Middleware::Session::Simple versions through 0.04 for Perl generates session ids insecurely
Summary
Plack::Middleware::Session::Simple versions through 0.04 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.
Plack::Middleware::Session::Simple is intended to be compatible with Plack::Middleware::Session, which had a similar security issue CVE-2025-40923.
Severity ?
9.8 (Critical)
CWE
Assigner
References
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| KAZEBURO | Plack::Middleware::Session::Simple |
Affected:
0 , ≤ 0.04
(custom)
|
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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