Amazon Ssm Agent
Monthly
SSRF in AWS Systems Manager Agent's port-forwarding feature allows an authenticated remote user to bypass the link-local address denylist and reach the EC2 Instance Metadata Service (IMDS), enabling theft of the managed instance's temporary IAM role credentials. The bypass exploits insufficient canonicalization of IP addresses before denylist evaluation - alternate representations of 169.254.169.254 (hex, decimal, IPv6-mapped, etc.) pass the check unblocked. With stolen credentials, the attacker can exercise the instance's full IAM role permissions from outside the instance. No public exploit identified at time of analysis, but the release notes confirm the fix explicitly canonicalizes IPs and extends the denylist to include ECS/EKS credential endpoints.
Path traversal in the aws:downloadContent plugin of amazon-ssm-agent before 3.3.4515.0 allows an authenticated attacker with a specifically scoped ssm:SendCommand IAM permission to write arbitrary files outside the intended download directory with root privileges on targeted managed instances. By directing the AWS-DownloadContent SSM document to retrieve from a controlled S3 source containing crafted object keys with path traversal sequences, an attacker can overwrite sensitive system files and escalate to full remote code execution as root. No public exploit code or CISA KEV listing has been identified at time of analysis, but the root-privilege arbitrary write primitive represents a high-impact capability in compromised-credential scenarios.
Amazon AWS amazon-ssm-agent before 3.1.1208.0 creates a world-writable sudoers file, which allows local attackers to inject Sudo rules and escalate privileges to root. Rated high severity (CVSS 7.0). Public exploit code available.
SSRF in AWS Systems Manager Agent's port-forwarding feature allows an authenticated remote user to bypass the link-local address denylist and reach the EC2 Instance Metadata Service (IMDS), enabling theft of the managed instance's temporary IAM role credentials. The bypass exploits insufficient canonicalization of IP addresses before denylist evaluation - alternate representations of 169.254.169.254 (hex, decimal, IPv6-mapped, etc.) pass the check unblocked. With stolen credentials, the attacker can exercise the instance's full IAM role permissions from outside the instance. No public exploit identified at time of analysis, but the release notes confirm the fix explicitly canonicalizes IPs and extends the denylist to include ECS/EKS credential endpoints.
Path traversal in the aws:downloadContent plugin of amazon-ssm-agent before 3.3.4515.0 allows an authenticated attacker with a specifically scoped ssm:SendCommand IAM permission to write arbitrary files outside the intended download directory with root privileges on targeted managed instances. By directing the AWS-DownloadContent SSM document to retrieve from a controlled S3 source containing crafted object keys with path traversal sequences, an attacker can overwrite sensitive system files and escalate to full remote code execution as root. No public exploit code or CISA KEV listing has been identified at time of analysis, but the root-privilege arbitrary write primitive represents a high-impact capability in compromised-credential scenarios.
Amazon AWS amazon-ssm-agent before 3.1.1208.0 creates a world-writable sudoers file, which allows local attackers to inject Sudo rules and escalate privileges to root. Rated high severity (CVSS 7.0). Public exploit code available.