CVE-2021-39155 log

Severity High
Remote Yes
Type Access restriction bypass
A security issue has been found in Istio before version 1.11.1. According to RFC 4343, Istio authorization policy should compare the hostname in the HTTP Host header in a case insensitive way, but currently the comparison is case sensitive. The proxy will route the request hostname in a case-insensitive way which means the authorization policy could be bypassed.

As an example, the user may have an authorization policy that rejects request with hostname "" for some source IPs, but the attacker can bypass this by sending the request with hostname "Httpbin.Foo".
Group Package Affected Fixed Severity Status Ticket
AVG-2321 istio 1.11.0-1 1.11.1-1 High Fixed