CVE-2025-40926 (GCVE-0-2025-40926)
Vulnerability from cvelistv5 – Published: 2026-03-05 01:24 – Updated: 2026-04-21 02:42
VLAI
EPSS
VEX
Title
Plack::Middleware::Session::Simple versions before 0.05 for Perl generates session ids insecurely
Summary
Plack::Middleware::Session::Simple versions before 0.05 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.
Predictable 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)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-05 16:28 UTC
CWE
Assigner
CPANSec
CNA
References
6 references
| URL | Tags |
|---|---|
| https://metacpan.org/release/KAZEBURO/Plack-Middl… | |
| https://github.com/kazeburo/Plack-Middleware-Sess… | issue-tracking |
| https://github.com/kazeburo/Plack-Middleware-Sess… | patch |
| https://www.cve.org/CVERecord?id=CVE-2025-40923 | vendor-advisoryrelatedvdb-entry |
| https://security.metacpan.org/docs/guides/random-… | technical-description |
| https://metacpan.org/release/KAZEBURO/Plack-Middl… | release-notes |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| KAZEBURO | Plack::Middleware::Session::Simple |
Affected:
0 , < 0.05
(custom)
|
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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