Bug 2493652 (CVE-2026-47220)

Summary: CVE-2026-47220 envoy: Envoy: Denial of Service via missing host header in specific logging configurations
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: kaycoth
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Envoy. A remote attacker can exploit this vulnerability by sending a request with a missing host header when the `%REQUESTED_SERVER_NAME(X:Y)%` is used in the log format and host-related options, such as HOST_FIRST or SNI_FIRST, are specified. This can lead to a crash of the Envoy proxy, resulting in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-26 19:01:58 UTC
Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37.5 and 1.38.3, when the %REQUESTED_SERVER_NAME(X:Y)% is used in log format and host related options is specified, like HOST_FIRST, SNI_FIRST, it's possible to crash Envoy when the specified host header is missing in the request headers. This vulnerability is fixed in 1.37.5 and 1.38.3.