NULL Pointer Dereference Affecting ecs-service-connect-agent package, versions <0:v1.39.1.0-1.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.74% (54th percentile)

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  • Snyk IDSNYK-AMZN2023-ECSSERVICECONNECTAGENT-19820168
  • published15 Sept 2026
  • disclosed21 Sept 2026

Introduced: 15 Sep 2026

CVE-2026-48521  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 ecs-service-connect-agent to version 0:v1.39.1.0-1.amzn2023 or higher.
This issue was patched in ALAS2023-2026-2149.

NVD Description

Note: Versions mentioned in the description apply only to the upstream ecs-service-connect-agent package and not the ecs-service-connect-agent package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

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.