CVE-2023-38493: Paths contain matrix variables bypass decorators

Impact

Spring supports Matrix variables. When Spring integration is used, Armeria calls Spring controllers via TomcatService or JettyService with the path that may contain matrix variables. In this situation, the Armeria decorators might not invoked because of the matrix variables. Let's see the following example:

// Spring controller
@GetMapping("/important/resources")
public String important() {...}

// Armeria decorator
ServerBuilder sb = ...
sb.decoratorUnder("/important/", authService);

If an attacker sends a request with /important;a=b/resources, the request would bypass the authrorizer

Patches

• https://github.com/line/armeria-ghsa-wvp2-9ppw-337j/commit/9b0ec3e099cc05fbff11d7f1012a1dddb0000d0c

Workarounds

Users can add decorators using regex. e.g. "regex:^/important.*"