Cross-site Scripting (XSS) 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
0.62% (48th percentile)

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  • Snyk IDSNYK-AMZN2023-ECSSERVICECONNECTAGENT-19821557
  • published15 Sept 2026
  • disclosed21 Sept 2026

Introduced: 15 Sep 2026

CVE-2026-73546  (opens in a new tab)
CWE-79  (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 /stats?format=html admin endpoint uses StatsHtmlRender, which sanitizes string statistic values but emits statistic names without HTML encoding. A data-plane component such as grpc_stats with stats_for_all_methods enabled can incorporate attacker-controlled path segments into cached dynamic statistic names. When an operator views the HTML stats page, the stored name can execute script with the admin interface's origin and issue privileged same-origin requests. The relevant scope boundary is that the admin interface must be browser-accessible and an enabled component must persist attacker-influenced text in statistic names. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.