{"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-2026-33248"],"ecosystem":"Go","epss":0.00149,"exploited":false,"fixed_versions":["2.11.15","2.12.6"],"ghsa_id":"GHSA-3f24-pcvm-5jqc","id":"tcs_01M5KGGBP8X9JHPK7Z7KRP0690","modified_at":"2026-03-27T18:26:05.115118Z","published_at":"2026-03-26T20:33:02Z","references":["https://osv.dev/vulnerability/GO-2026-4828","https://github.com/nats-io/nats-server/security/advisories/GHSA-3f24-pcvm-5jqc","https://advisories.nats.io/CVE/secnote-2026-13.txt"],"severity":{"label":"medium","score":4.2},"sources":[{"source":"osv","source_id":"GO-2026-4828#Go/github.com/nats-io/nats-server/v2","url":"https://osv.dev/vulnerability/GO-2026-4828"},{"source":"nvd","source_id":"CVE-2026-33248","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33248"}],"summary":"NATS has mTLS verify_and_map authentication bypass via incorrect Subject DN matching in github.com/nats-io/nats-server"}