CPANSA-Concierge-Sessions-2026-2439: Concierge-Sessions vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-02-16T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-02-16T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 9.8 Severity
Original language Language en
Also referred to

Vulnerability Description

Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids. The generate_session_id function in Concierge::Sessions::Base defaults to using the uuidgen command to generate a UUID, with a fallback to using Perl's built-in rand function. Neither of these methods are secure, and attackers are able to guess session_ids that can grant them access to systems. Specifically, * There is no warning when uuidgen fails. The software can be quietly using the fallback rand() function with no warnings if the command fails for any reason. * The uuidgen command will generate a time-based UUID if the system does not have a high-quality random number source, because the call does not explicitly specify the --random option. Note that the system time is shared in HTTP responses. * UUIDs are identifiers whose mere possession grants access, as per RFC 9562. * The output of the built-in rand() function is predictable and unsuitable for security applications.

Vulnerabilities

CVE-2026-2439

Vulnerability Description

Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids. The generate_session_id function in Concierge::Sessions::Base defaults to using the uuidgen command to generate a UUID, with a fallback to using Perl's built-in rand function. Neither of these methods are secure, and attackers are able to guess session_ids that can grant them access to systems. Specifically,

* There is no warning when uuidgen fails. The software can be quietly using the fallback rand() function with no warnings if the command fails for any reason.
* The uuidgen command will generate a time-based UUID if the system does not have a high-quality random number source, because the call does not explicitly specify the --random option. Note that the system time is shared in HTTP responses.
* UUIDs are identifiers whose mere possession grants access, as per RFC 9562.
* The output of the built-in rand() function is predictable and unsuitable for security applications.

Weakness CWE-338 : Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Product status

Known affected
Product Score
Concierge-Sessions greater than or equal 0.8.1 and less than 0.8.5
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 9.8 Critical
Fixed

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Mon Feb 16 00:00:00 2026 First release

Sharing rules

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