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TI-2025-27317 Aliases CVE-2025-40926GHSA-g98h-c5v8-8m3f

Plack::Middleware::Session::Simple versions before 0.05 for Perl generates session ids…

Priority MEDIUM 49CWE-338Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00503 43rd percentileScored 2026-11-07
Fix Fixed Plack::Middleware::Session::Simple (KAZEBURO): 0.05

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
KAZEBUROPlack::Middleware::Session::Simplebefore 0.050.05Patch availableCNA
  • Plack::Middleware::Session::Simple VendorKAZEBURO Affected before 0.05 Fixed in 0.05 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kazeburo:plack\:\:middleware\:\:session\:\:simple:*:*:*:*:*:perl:*:* middleware\VulnerableKAZEBURO
  • cpe:2.3:a:kazeburo:plack\:\:middleware\:\:session\:\:simple:*:*:*:*:*:perl:*:* Versions middleware\ Vulnerable ·KAZEBURO

Remediation

  • Fix · CNA Plack::Middleware::Session::Simple (KAZEBURO) Fixed in 0.05

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-40926
  2. 2026-10-03 Alias added: GHSA-g98h-c5v8-8m3f

References

Patch 2

Advisory 2

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences