CVE-2019-18838

An issue was discovered in Envoy 1.12.0. Upon receipt of a malformed HTTP request without a Host header, it sends an internally generated "Invalid request" response. This internally generated response is dispatched through the configured encoder filter chain before being sent to the client. An encoder filter that invokes route manager APIs that access a request's Host header causes a NULL pointer dereference, resulting in abnormal termination of the Envoy process.

• CWE-476

• https://blog.envoyproxy.ioProduct
• https://github.com/envoyproxy/envoy/commits/masterPatch
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-f2rv-4w6x-rwhcExploit, Third Party Advisory
• https://groups.google.com/forum/#%21forum/envoy-users
• https://blog.envoyproxy.ioProduct
• https://github.com/envoyproxy/envoy/commits/masterPatch
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-f2rv-4w6x-rwhcExploit, Third Party Advisory
• https://groups.google.com/forum/#%21forum/envoy-users

Published

Dec 13, 2019

Last Modified

Jun 17, 2026

Status

Modified

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