Off-by-one Error Affecting ecs-service-connect-agent package, versions <0:v1.34.13.0-1.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.37% (29th percentile)

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  • Snyk IDSNYK-AMZN2023-ECSSERVICECONNECTAGENT-15921328
  • published7 Apr 2026
  • disclosed10 Mar 2026

Introduced: 10 Mar 2026

CVE-2026-26309  (opens in a new tab)
CWE-193  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 ecs-service-connect-agent to version 0:v1.34.13.0-1.amzn2023 or higher.
This issue was patched in ALAS2023-2026-1532.

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 a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, an off-by-one write in Envoy::JsonEscaper::escapeString() can corrupt std::string null-termination, causing undefined behavior and potentially leading to crashes or out-of-bounds reads when the resulting string is later treated as a C-string. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.

CVSS Base Scores

version 3.1