CVE-2026-67990

Medium severity, CVSS 5.4. EPSS: 0.2% chance of exploitation in the next 30 days.

basecamp/upright at commit efe4f2e5254ac6e57e45d2261804cca74dbbca3f disables Rails CSRF protection for its Alertmanager and Prometheus proxy controllers. An unauthenticated attacker can induce a logged-in user's browser to submit requests that are forwarded to enabled upstream write or management endpoints, such as creating an Alertmanager silence or requesting a Prometheus reload. The final impact depends on the APIs enabled by the upstream services.

Published 2026-08-13. Last modified 2026-09-08.