Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3350
Advisory Released Date: 2026-06-08
Advisory Updated Date: 2026-10-14
When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 0. (CVE-2026-33814)
Improper limitation of a pathname to a restricted directory in the aws:downloadContent plugin in amazon-ssm-agent before 3.3.4515.0 might allow an authenticated remote user whose ssm:SendCommand permission is restricted to the AWS-DownloadContent document, to write arbitrary files outside the intended download directory with root privileges, via crafted object keys in the S3 source the document is directed to retrieve. This issue may lead to arbitrary code execution as root if specific sensitive files are overwritten.
To remediate this issue, customers should upgrade amazon-ssm-agent to version 3.3.4515.0 or later. (CVE-2026-81849)
Affected Packages:
amazon-ssm-agent
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update amazon-ssm-agent or yum update --advisory ALAS2-2026-3350 to update your system.
aarch64:
amazon-ssm-agent-3.3.4515.0-1.amzn2.aarch64
src:
amazon-ssm-agent-3.3.4515.0-1.amzn2.src
x86_64:
amazon-ssm-agent-3.3.4515.0-1.amzn2.x86_64
2026-10-14: CVE-2026-81849 was added to this advisory.