{"id":"CVE-2023-40577","aliases":["BIT-alertmanager-2023-40577","GHSA-v86x-5fm3-5p7j","GO-2023-2020"],"url":"https://o3.security/vulnerability/CVE-2023-40577","summary":"Alertmanager UI is vulnerable to stored XSS via the /api/v1/alerts endpoint","details":"Alertmanager handles alerts sent by client applications such as the Prometheus server. An attacker with the permission to perform POST requests on the /api/v1/alerts endpoint could be able to execute arbitrary JavaScript code on the users of Prometheus Alertmanager. This issue has been fixed in Alertmanager version 0.2.51.","published":"2023-08-25T00:12:13.045Z","modified":"2026-08-12T03:51:42.066556277Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/prometheus/alertmanager","fixedVersion":"0.25.1"}],"fix":null,"references":[{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2023/10/msg00011.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/40xxx/CVE-2023-40577.json"},{"type":"ADVISORY","url":"https://github.com/prometheus/alertmanager/security/advisories/GHSA-v86x-5fm3-5p7j"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-40577"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:42.066556277Z"}}