CVE-2026-2439

9.8 CRITICAL 0.5% exploit odds Fix listed Other

What it is

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.

At a glance

Exploitability: Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
Exploit odds: 0.5% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-02-16 22:22 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-06-17 10:30 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.5% in the next 30 days (EPSS).
Severity: 9.8 CRITICAL (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2026-02-16 22:22 UTC
Last modified: 2026-06-17 10:30 UTC
Exploit probability: 0.5% · EPSS, next 30 days
Weakness: CWE-338
Record status: Analyzed

Affected

Bva concierge\ < 0.8.5

Attack profile CVSS 3.1 · 9.8

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-2439.md and follow it. Check whether this project is affected by CVE-2026-2439. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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Fix and advisories

https://github.com/bwva/Concierge-Sessions/commit/20bb28e92e8fba307c4ff8264701c215be65e73b

References

NVD record · CVE.org record