CVE-2026-45692 Caddy: Remote Admin Authorization Bypass in `/config` API via Array Index Normalization
Attackers can bypass authorization checks on the Caddy admin API to modify configuration objects due to inconsistent path parsing between authorization and traversal layers.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45692?
CVE-2026-45692 is a medium-severity authentication bypass vulnerability in caddyserver caddy, published on 23 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Caddy is an extensible server platform that uses TLS by default. From 2.4.0 until 2.11.3, the authorization layer and the /config traversal layer do not agree on what object the path refers to. In this case, a path authorized for one config object is accepted, but then resolves to a different config object during traversal. This happens because the authorization layer uses string prefix matching and the /config traversal layer parses array indices numerically using strconv.Atoi(). This vulnerability is fixed in 2.11.3.
Which versions are affected by CVE-2026-45692?
3 open source packages ship an affected version, including github.com/caddyserver/caddy/v2. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/caddyserver/caddy/v2 Go | From 2.4.0 | 2.11.3 |
github.com/caddyserver/caddy/v2 Go | From 2.4.0 | 2.11.3 |
github.com/caddyserver/caddy/v2 Go | From 2.4.0 | 2.11.3 |
Products include Caddyserver Caddy.
How do I fix CVE-2026-45692?
Upgrade github.com/caddyserver/caddy/v2 to 2.11.3 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-45692 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45692 exists.
Other vulnerabilities in caddyserver caddy
- CVE-2018-21246 Caddy vulnerable to Authentication Bypass due to mishandling of TLS client authentication
- CVE-2026-27590 Caddy: Unicode case-folding length expansion causes incorrect split_path index in FastCGI transport
- CVE-2026-27586 Caddy's mTLS client authentication silently fails open when CA certificate file is missing or malformed
- CVE-2026-45135 Caddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP Files
- CVE-2026-52845 Caddy: FastCGI header normalization bypass in `forward_auth copy_headers`
Sources
Also known as CLEANSTART-2026-WK22640, DEBIAN-CVE-2026-45692, GHSA-x5w9-xh9r-mvfc, GO-2026-5743, MINI-ff5f-x2fr-4vxm, MINI-x239-2ffx-m95m and 1 more.