Description
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's ProdClusterManagerFactory::allocateConnPool dereferences transport_socket_options while selecting an HTTP/3 connection pool without first checking whether the pointer is null. LoadBalancerContext implementations used by synthetic, mirror, health-check, and async-client calls can return no transport-socket options. With auto_config and HTTP/3 enabled, routine traffic reaching one of those contexts can crash an Envoy worker. The relevant scope boundary is that the affected branch requires HTTP/3 in the protocol set and a context that supplies no transport-socket options. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.
Affected products
envoyproxy: envoy
References10
- github.com/envoyproxy/envoy/security/advisories/GHSA-5vff-j9p4-… ExploitVendor Advisory
- github.com/envoyproxy/envoy/security/advisories/GHSA-5vff-j9p4-… ExploitVendor Advisory
- github.com/envoyproxy/envoy/commit/8ef2da8527fcd17388b046c1add4… Patch
- github.com/envoyproxy/envoy/commit/cec4899acf03cf551f28611a5f32… Patch
- github.com/envoyproxy/envoy/commit/e7b4839beef7f43594ce8e94c456… Patch
- github.com/envoyproxy/envoy/commit/f5436f44103fb14cb8ba42a8db0f… Patch
- github.com/envoyproxy/envoy/releases/tag/v1.36.10 Release Notes
- github.com/envoyproxy/envoy/releases/tag/v1.37.6 Release Notes
- github.com/envoyproxy/envoy/releases/tag/v1.38.4 Release Notes
- github.com/envoyproxy/envoy/releases/tag/v1.39.1 Release Notes
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 8 November 2026
- CWE
- CWE-476
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