{"id":"CVE-2026-91165","published":"2026-09-21T19:17:15.190","lastModified":"2026-09-21T20:17:39.473","description":"Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.27.6, the response_mode=form_post SSO return path in warpgate-protocol-http/src/api/sso_provider_list.rs uses serde_json::to_string inside ReturnToSsoPostResponse without neutralizing a script-closing sequence. The vulnerable value can enter the script block through the attacker-controlled next redirect parameter stored by warpgate-protocol-http/src/api/sso_provider_detail.rs or through IdP-derived error messages that make_redirect_url concatenates without URL encoding. The IdP-derived path is reachable when the attacker controls a configured identity provider, or when the attacker controls the email or username claim on an attacker-controlled account and the configured identity provider permits the required unvalidated claim format. A victim must complete the form_post SSO flow for the injected markup to be rendered. The Warpgate Content-Security-Policy blocks injected JavaScript and event handlers, so the demonstrated impact is content spoofing, a false login form, or a meta refresh rather than script execution. This issue is fixed in version 0.27.6.","cvssScore":2.4,"cvssSeverity":"LOW","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:L/A:N","cwes":["CWE-79"],"vendors":[],"products":[],"references":[{"url":"https://github.com/warp-tech/warpgate/commit/e94425a08f501383a67316673749dcbd637c6ce3","tags":[]},{"url":"https://github.com/warp-tech/warpgate/releases/tag/v0.27.6","tags":[]},{"url":"https://github.com/warp-tech/warpgate/security/advisories/GHSA-vvpj-p7j8-4rv4","tags":[]}],"exploitRefs":[{"url":"https://github.com/warp-tech/warpgate/commit/e94425a08f501383a67316673749dcbd637c6ce3","tags":[]},{"url":"https://github.com/warp-tech/warpgate/releases/tag/v0.27.6","tags":[]},{"url":"https://github.com/warp-tech/warpgate/security/advisories/GHSA-vvpj-p7j8-4rv4","tags":[]}],"hasPoc":true,"ai":null}