Amazon Linux 2 : ecs-service-connect-agent (ALASECS-2026-155)

medium Nessus Plugin ID 374362

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of ecs-service-connect-agent installed on the remote host is prior to v1.39.4.0-1. It is, therefore, affected by a vulnerability as referenced in the ALAS2ECS-2026-155 advisory.

Issue summary: A certificate with many nameRelativeToCRLIssuer CRLdistribution points causes disproportionate heap growth when OpenSSL cachesX.509 extensions.

Impact summary: Receiving a crafted certificate from a malicious peer can leadto significant memory pressure and possible Denial of Service in clients orin servers that solicit client certificates.

CWE: CWE-770: Allocation of Resources Without Limits or Throttling

Description: A certificate or a set of certificates that fits under the limit forsize of certificates accepted from the peer (~100 KiB) can result in allocationof several hundred MiB of resident memory on the receiving sideduring a normal TLS handshake. This may be enough to crash the client orserver, if multiple concurrent connections lead to similarly large memoryallocations.

The fix postpones processing of the CRL distribution points extensions incertificates to the time when the processed value is required for CRL processing.This avoids keeping large memory allocations for a long time when suchcertificates are received.

FIPS impact: noThe affected code is outside the FIPS module boundary. (CVE-2026-35189)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update ecs-service-connect-agent' or or 'yum update --advisory ALAS2ECS-2026-155' to update your system.

Plugin Details

Severity: Medium

ID: 374362

File Name: al2_ALASECS-2026-155.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 10/30/2026

Updated: 10/30/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2026-35189

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:ecs-service-connect-agent

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 10/30/2026

Vulnerability Publication Date: 9/29/2026

Reference Information

CVE: CVE-2026-35189

Detections

Analytics