Tinyauth: forward-auth per-app ACL is matched case-sensitively against the (case-insensitive) hostname, letting an authenticated user reach apps they are not on the allowlist for
# tinyauth: forward-auth per-app ACL is matched case-sensitively against the (case-insensitive) hostname, letting an authenticated user reach apps they are not on the allowlist for ## GitHub Advisory Details (form fields — paste-ready) **Affected products** | Field | Value | |-------|-------| | Ecosystem | `Other (self-hosted)` / Go | | Package name | `github.com/steveiliop56/tinyauth` (forward-auth middleware) | | Affected versions | `< 5.1.2` | | Patched versions | `5.1.2` | **Advisory details** | Field | Value | |-------|-------| | Title | tinyauth forward-auth authorization bypass: per-app ACL host matching is case-sensitive while hostnames are case-insensitive, so a mixed-case host defeats `users`/`groups`/`ip` allowlists and fails open | - **Status:** Runtime-confirmed (local lab, 127.0.0.1 only) - **Target:** steveiliop56/tinyauth `v5.0.7` (commit `479f1657812b7bf01438607464dedaa148155301`); root cause also present on `main` HEAD - **Component:** `internal/service/access_controls_service.go` (`lookupStaticACLs` / `GetAccessControls`), `internal/service/docker_service.go` (`GetLabels`), `internal/controller/proxy_controller.go` (`proxyHandler`) - **Class:** Broken access control / authorization bypass across the per-app trust boundary ## Summary tinyauth is a forward-auth service: a reverse proxy (Traefik/Caddy/nginx/Envoy) calls `GET /api/auth/` on every request and only forwards the request upstream if tinyauth returns `200`. tinyauth decides *which* per-app access ru
GHSA-328g-jx67-v94g
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:GHSA-328g-jx67-v94g
github.com/tinyauthapp/tinyauth
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 1.0.1-0.20260720133915-80bc87188ec3
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "SEMVER",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.1-0.20260720133915-80bc87188ec3"
}
]
}
],
"package": {
"name": "github.com/tinyauthapp/tinyauth",
"purl": "pkg:golang/github.com/tinyauthapp/tinyauth",
"ecosystem": "Go"
},
"database_specific": {
"source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-328g-jx67-v94g/GHSA-328g-jx67-v94g.json"
}
}
]- Related CVEs
- CVE-2026-77560
Source reference:
/aliases
Publisher severity
high
Source reference: /database_specific/severity
- Event
- #63976 · Revision 1
- Added to Heist Feed
- Publisher date