CVE-2026-57294
Description
A missing permission check in Jenkins EC2 Fleet Plugin 4.2.3.539.v8fedff2a_81c3 and earlier allows attackers with Overall/Read permission to connect to an attacker-specified URL using attacker-specified credentials IDs obtained through another method, capturing AWS credentials stored in Jenkins.
Summary dbcve.org
The EC2 Fleet Plugin lacks permission checks on a feature that allows connection to user-specified URLs using user-specified credential IDs. Attackers with only Overall/Read permission (the lowest privilege) can exploit this to direct Jenkins to connect to malicious URLs and exfiltrate AWS credentials stored in the system.
Mitigation
Upgrade EC2 Fleet Plugin to a version beyond 4.2.3.539.v8fedff2a_81c3 which includes the permission check, or restrict Overall/Read permission to trusted users only until patching is feasible.