{"cve":"CVE-2026-101090","nvd":{"published":"2026-09-27T21:17:03.003","modified":"2026-09-28T21:02:16.150","status":"Deferred","description":"Nezha 2.2.3 contains a Host header injection regression in the OAuth2 redirect endpoint. When the new optional dashboard_host setting is empty, /api/v1/oauth2/{provider} (cmd/dashboard/controller/oauth2.go) reflects the attacker-supplied HTTP Host header into the redirect_uri sent to the identity provider instead of falling back to the configured install_host. An attacker who induces a victim to begin OAuth2 login via a request that reaches Nezha with a forged Host header can cause an attacker-controlled callback URL to be used as the redirect_uri; if the OAuth2 provider accepts it, the victim's authorization code is delivered to the attacker origin, allowing the attacker to complete the OAuth2 login/binding flow and take over the account. This regresses the fix for GHSA-9rc6-8cjv-rcvx and is configuration-dependent (dashboard_host empty). At the time of the advisory no patched version was available.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":9.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-601"],"references":["https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7","https://www.vulncheck.com/advisories/nezha-through-2.2.3-host-header-injection-via-oauth2-redirect-uri","https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-101090","score":0.00443,"percentile":0.38565,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-rf68-8gjr-36q7","url":"https://osv.dev/vulnerability/GHSA-rf68-8gjr-36q7","summary":"Nezha: OAuth2 redirect_uri Host header injection regression when dashboard_host is empty","modified":"2026-09-28T17:11:14.221598075Z","packages":[{"ecosystem":"Go","name":"github.com/nezhahq/nezha","purl":"pkg:golang/github.com/nezhahq/nezha","ranges":["2.2.3"],"fixed":[]}]},{"id":"GO-2026-6486","url":"https://osv.dev/vulnerability/GO-2026-6486","summary":"Nezha: OAuth2 redirect_uri Host header injection regression when dashboard_host is empty in github.com/nezhahq/nezha","modified":"2026-09-28T17:11:14.221598075Z","packages":[{"ecosystem":"Go","name":"github.com/nezhahq/nezha","purl":"pkg:golang/github.com/nezhahq/nezha","ranges":["all versions"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}