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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-40926 Detail

Current Description

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.


View Analysis Description

Metrics

 
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CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/kazeburo/Plack-Middleware-Session-Simple/commit/760bb358b8f53e52cf415888a4ac858fd99bb24e.patch CPANSec Patch 
https://github.com/kazeburo/Plack-Middleware-Session-Simple/pull/4 CPANSec Issue Tracking  Patch 
https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.04/source/lib/Plack/Middleware/Session/Simple.pm#L43 CPANSec Issue Tracking  Product 
https://metacpan.org/release/KAZEBURO/Plack-Middleware-Session-Simple-0.05/changes CPANSec
https://security.metacpan.org/docs/guides/random-data-for-security.html CPANSec Third Party Advisory 
https://www.cve.org/CVERecord?id=CVE-2025-40923 CPANSec Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) CPANSec  
CWE-340 Generation of Predictable Numbers or Identifiers CPANSec  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-40926
NVD Published Date:
03/04/2026
NVD Last Modified:
03/11/2026
Source:
CPANSec