{"id":"CVE-2020-26521","aliases":["GHSA-h2fg-54x9-5qhq","GHSA-hmm9-r2m2-qg9w","GO-2022-0402"],"url":"https://o3.security/vulnerability/CVE-2020-26521","summary":"Nil dereference in NATS JWT, DoS of nats-server","details":"The JWT library in NATS nats-server before 2.1.9 allows a denial of service (a nil dereference in Go code).","published":"2020-11-06T08:15:13.563Z","modified":"2026-07-08T05:55:59.603387224Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.02116,"percentile":0.80165,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/nats-io/jwt","fixedVersion":"1.1.0"}],"fix":null,"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VT67XCLIIBYRT762SVFBYFFTQFVSM3SI/"},{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2020/11/02/2"},{"type":"FIX","url":"https://github.com/nats-io/nats-server/commits/master"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-08T05:55:59.603387224Z"}}