Use After Free Affecting ecs-service-connect-agent package, versions <0:v1.39.1.0-1.amzn2023
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-AMZN2023-ECSSERVICECONNECTAGENT-19821567
- published15 Sept 2026
- disclosed21 Sept 2026
Introduced: 15 Sep 2026
CVE-2026-73512 (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 HttpDatagramHandler caches the current RequestDecoder when Capsule Protocol is enabled. Stream recreation, including an internal redirect, replaces the ActiveStream and updates EnvoyQuicServerStream but does not update the handler's cached pointer. A subsequent HTTP/3 datagram can call decodeData through the freed decoder, causing invalid virtual dispatch and a process crash. The relevant scope boundary is that hTTP/3 datagrams and Capsule Protocol must be enabled, and the request must enter a stream-recreation path such as an internal redirect. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.
References
- http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-73512
- https://github.com/envoyproxy/envoy/commit/29dbaae4a9971011e2f1948acfaf383296e901ea
- https://github.com/envoyproxy/envoy/commit/85495163fdc67364a5258bfe478c34a44f6428b4
- https://github.com/envoyproxy/envoy/commit/c0e46dabc3ac286bbe608e9274776555911aadb9
- https://github.com/envoyproxy/envoy/commit/f2417eec2ff49abe243d484ded916fbc2faca38d
- 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
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-r6j2-mrm5-72mg