CVE-2026-48521
Envoy: HTTP/3 connection pool selection null-derefs in ProdClusterManagerFactory::allocateConnPool when transport_socket_options is null
- State
- Published
- Severity
- 5.9 Medium
- Published
- Sep 21, 2026
- Updated
- Sep 21, 2026
- Reserved
- May 21, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.9 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-476 NULL Pointer Dereference
Affected Products
| Product | Versions |
|---|---|
envoyenvoyproxy |
|
References
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-5vff-j9p4-38j3
- https://github.com/envoyproxy/envoy/commit/8ef2da8527fcd17388b046c1add4fb47fb5d0868
- https://github.com/envoyproxy/envoy/commit/cec4899acf03cf551f28611a5f32385648d95f96
- https://github.com/envoyproxy/envoy/commit/e7b4839beef7f43594ce8e94c4563c80db04a8a7
- https://github.com/envoyproxy/envoy/commit/f5436f44103fb14cb8ba42a8db0f54a06c98c45a
- https://github.com/envoyproxy/envoy/releases/tag/v1.36.10
- https://github.com/envoyproxy/envoy/releases/tag/v1.37.6
- https://github.com/envoyproxy/envoy/releases/tag/v1.38.4
- https://github.com/envoyproxy/envoy/releases/tag/v1.39.1
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