{"id":"GHSA-8wx9-j7j5-h9vp","summary":"Duplicate Advisory: Localhost-trust admin bypass on auth-code-gated endpoints, with potential remote reachability via the fixed-port prox","details":"## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-3mp7-4rh5-jrv9. This link is maintained to preserve external references.\n\n## Original Description\nSiYuan versions \u003c= v3.7.2 (patched in v3.7.4) contain an authentication bypass vulnerability in the kernel's CheckAuth function, which grants the administrator role (RoleAdministrator) to any request whose RemoteAddr is loopback (127.0.0.1) for a specific set of endpoints (including /api/system/exit, getNetwork, getWorkspaceInfo, /assets/*, and /export/*). These localhost bypasses sit outside the access auth code gate, so they apply even when an access auth code is configured. Because the fixed-port reverse proxy forwards requests to the kernel over loopback without injecting an authentication token and does not configure trusted proxies, a request forwarded through this proxy reaches the kernel with RemoteAddr = 127.0.0.1. If the fixed-port proxy is bound to a network interface, this could allow a remote unauthenticated attacker to obtain admin access on the affected endpoints; however, per the advisory this remote forwarding behavior was established only by code inspection and was not reproduced end-to-end.","modified":"2026-09-03T22:45:04.767621542Z","published":"2026-08-12T21:31:42Z","withdrawn":"2026-09-03T22:32:26Z","database_specific":{"cwe_ids":["CWE-290"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-09-03T22:32:26Z","nvd_published_at":"2026-08-12T20:17:53Z"},"references":[{"type":"WEB","url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3mp7-4rh5-jrv9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72809"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-localhost-trust"}],"affected":[{"package":{"name":"github.com/siyuan-note/siyuan/kernel","ecosystem":"Go","purl":"pkg:golang/github.com/siyuan-note/siyuan/kernel"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"database_specific":{"last_known_affected_version_range":"\u003c 3.7.4","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-8wx9-j7j5-h9vp/GHSA-8wx9-j7j5-h9vp.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}