CVE-2026-44595

Yamcs: Unauthorized user enumeration via IAM API endpoints

CVSS 4.3 MEDIUMCWE-862

Vexday Risk Score

10Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 4.3EPSS —KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

16 Jul 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

Yamcs is a mission control framework. Prior to 5.12.7, the IAM API endpoints listUsers, getUser, listGroups, and getGroup in yamcs-core did not enforce the required SystemPrivilege.ControlAccess check in yamcs-core/src/main/java/org/yamcs/http/api/IamApi.java, so any authenticated user, even one with low or no privileges, could enumerate all user accounts in the system including their usernames, superuser status, and group memberships. This issue is fixed in versions 5.12.7 and 5.13.0.

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

Affected products

yamcs · yamcs

References

https://github.com/yamcs/yamcs/commit/0e12b518f103f24681299318a30a460fe4327b88 https://github.com/yamcs/yamcs/commit/e90099fba98e96214217c195b6a5b87b5f46e51c https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.7 https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.0 https://github.com/yamcs/yamcs/security/advisories/GHSA-p2rj-mrmc-9w29