{"action":"Upgrade github.com/nats-io/nats-server/v2 to 2.11.15 or later.","affected":[{"fixed":"2.11.15","introduced":"0"},{"fixed":"2.12.6","introduced":"2.12.0-RC.1"}],"component":"github.com/nats-io/nats-server/v2","cve_ids":["CVE-2026-33217"],"ecosystem":"Go","epss":0.00264,"exploited":false,"fixed_versions":["2.11.15","2.12.6"],"ghsa_id":"GHSA-jxxm-27vp-c3m5","id":"tcs_01M5KGGDZJXK51R4YAKW1PFDFQ","modified_at":"2026-03-27T18:25:58.731890Z","published_at":"2026-03-26T20:33:05Z","references":["https://osv.dev/vulnerability/GO-2026-4834","https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5","https://advisories.nats.io/CVE/secnote-2026-07.txt"],"severity":{"label":"medium","score":6.5},"sources":[{"source":"osv","source_id":"GO-2026-4834#Go/github.com/nats-io/nats-server/v2","url":"https://osv.dev/vulnerability/GO-2026-4834"},{"source":"nvd","source_id":"CVE-2026-33217","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33217"}],"summary":"NATS allows MQTT clients to bypass ACL checks in github.com/nats-io/nats-server"}