{"id":"CVE-2026-53523","aliases":["GHSA-9rc6-8cjv-rcvx","GO-2026-5829"],"url":"https://o3.security/vulnerability/CVE-2026-53523","summary":"Nezha Monitoring: OAuth2 Redirect URL — Host Header Injection","details":"Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 1.0.0 to before version 2.2.0, the getRedirectURL function in oauth2.go:22-29 constructs the OAuth2 callback URL by concatenating the request's Host header with a fixed path, with zero validation of the Host header. This can result in host header injection. This issue has been patched in version 2.2.0.","published":"2026-06-12T21:04:46.741Z","modified":"2026-08-07T11:51:18.923084881Z","cvss":{"score":6.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/nezhahq/nezha","fixedVersion":"2.2.0"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53523.json"},{"type":"ADVISORY","url":"https://github.com/nezhahq/nezha/security/advisories/GHSA-9rc6-8cjv-rcvx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53523"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:51:18.923084881Z"}}