Envoy · Envoy · CVE-2019-18802
**Name of the Vulnerable Software and Affected Versions**
Envoy version 1.12.0
**Description**
An issue was discovered where an untrusted remote client can send an HTTP header, such as the `Host` header, with whitespace after the header content. This allows the client to bypass matchers, for example, by sending a `Host` header with a value of "example.com " to bypass an "example.com" matcher.
**Recommendations**
For Envoy version 1.12.0, as a temporary workaround, consider restricting the use of HTTP headers with whitespace after the header content until a patch is available.