CVE-2026-2439 (GCVE-0-2026-2439)
Vulnerability from cvelistv5 – Published: 2026-02-16 21:25 – Updated: 2026-02-17 14:45
VLAI
EPSS
VEX
Title
Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids
Summary
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.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-17 14:44 UTC
CWE
Assigner
CPANSec
CNA
References
5 references
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| BVA | Concierge::Sessions |
Affected:
0.8.1 , < 0.8.5
(custom)
|
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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