CVE-2026-73293Semaphore UI: Manager-to-owner privilege escalation via custom-role slug collision

Description

Semaphore UI is a web interface for managing DevOps tools. Prior to 2.18.19 and from 2.19.0-alpha3 until 2.19.5-beta5, ProjectMiddleware and GetProjectOrGlobalRoleBySlug allow a project manager to use POST /api/project/{id}/roles to create a custom manager role with permission bitmask 15, overriding the built-in manager permissions and granting CanUpdateProject and CanManageProjectUsers owner capabilities. This issue is fixed in versions 2.18.19 and 2.19.5-beta5.

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

References and patches

• https://github.com/semaphoreui/semaphore/security/advisories/GHSA-cxvf-gvfq-36w2
• https://github.com/semaphoreui/semaphore/commit/1c4bb65df114962134f8829d4a03667106a01a68
• https://github.com/semaphoreui/semaphore/commit/bb2a4e1f08c8023e618f8dd6eaca73554f2c33bb
• https://github.com/semaphoreui/semaphore/releases/tag/v2.18.19
• https://github.com/semaphoreui/semaphore/releases/tag/v2.19.5-beta5