CVE-2026-32136
AdGuard Home: HTTP/2 Cleartext (h2c) Upgrade Authentication Bypass
Severity by source
Trivy's own label is CRITICAL. Rated critical by GHSA.
Description
AdGuard Home is a network-wide software for blocking ads and tracking. Prior to 0.107.73, an unauthenticated remote attacker can bypass all authentication in AdGuardHome by sending an HTTP/1.1 request that requests an upgrade to HTTP/2 cleartext (h2c). Once the upgrade is accepted, the resulting HTTP/2 connection is handled by the inner mux, which has no authentication middleware attached. All subsequent HTTP/2 requests on that connection are processed as fully authenticated, regardless of whether any credentials were provided. This vulnerability is fixed in 0.107.73.
Affected packages and fixed versions
| Source | Package | Fixed in |
|---|---|---|
| go::GitHub Security Advisory Go | github.com/AdguardTeam/AdGuardHome | 0.107.73 |