Related Vulnerabilities: CVE-2017-1000354  

The login command available in the remoting-based CLI stored the encrypted user name of the successfully authenticated user in a cache file used to authenticate further commands. Users with sufficient permission to create secrets in Jenkins, and download their encrypted values (e.g. with Job/Configure permission), were able to impersonate any other Jenkins user on the same instance. This has been fixed by storing the cached authentication as a hash-based MAC with a key specific to the Jenkins instance and the CLI authentication cache. Previously cached authentications are invalidated when upgrading Jenkins to a version containing a fix for this.

Severity High

Remote Yes

Type Privilege escalation

Description

The login command available in the remoting-based CLI stored the encrypted user name of the successfully authenticated user in a cache file used to authenticate further commands. Users with sufficient permission to create secrets in Jenkins, and download their encrypted values (e.g. with Job/Configure permission), were able to impersonate any other Jenkins user on the same instance.

This has been fixed by storing the cached authentication as a hash-based MAC with a key specific to the Jenkins instance and the CLI authentication cache.

Previously cached authentications are invalidated when upgrading Jenkins to a version containing a fix for this.

AVG-255 jenkins 2.56-1 2.57-1 High Fixed

27 Apr 2017 ASA-201704-8 AVG-255 jenkins High multiple issues

https://jenkins.io/security/advisory/2017-04-26/