23 Oct 2026 15:48:27 UTC
Warpgate: Reflected XSS in SSO return endpoint via attacker-controlled next parameter
cve-program · CVE-2026-58491 · Published
CVE-2026-58491
Warpgate: Reflected XSS in SSO return endpoint via attacker-controlled next parameter
CVSS 3.1 9.3 CRITICALCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-58491
PublishedWarpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. Prior to 0.25.5, the /@warpgate/api/sso/providers/:name/start endpoint stores an attacker-controlled next parameter that the POST /@warpgate/api/sso/return handler inserts without HTML escaping into the response generated by warpgate-protocol-http/src/api/sso_provider_list.rs. A victim who follows a crafted link and completes SSO can cause markup and JavaScript to execute in the authenticated Warpgate origin, allowing access to session data and actions through user APIs, and through administrator APIs only when the victim is an administrator. The GET /@warpgate/api/sso/return path also uses the same unvalidated value as a redirect destination, enabling an open redirect. This issue is fixed in version 0.25.5.
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