In Jenkins 2.567 and earlier, LTS 2.555.2 and earlier, it is possible for attackers to have Jenkins deserialize arbitrary types defined in Jenkins core or plugins from an attacker-controlled `config.xml` submission in a way that allows them to handle HTTP requests afterwards.
This can be used to impersonate any user and send HTTP requests on their behalf, up to and including use of the Script Console to run arbitrary code, or to read arbitrary files from the Jenkins controller.
Jenkins 2.567 and earlier, LTS 2.555.2 and earlier improperly determines that a redirect URL after login is legitimately pointing to Jenkins when it contains relative path segments (`./` or `../`), allowing attackers to perform phishing attacks.
Jenkins 2.567 and earlier, LTS 2.555.2 and earlier improperly determines that a redirect URL after login is legitimately pointing to Jenkins when it contains tab or newline characters between `//`, allowing attackers to perform phishing attacks.
A missing permission check in Jenkins 2.567 and earlier, LTS 2.555.2 and earlier allows attackers with Item/Cancel permission, but lacking Item/Read permission, to cancel queue items they do not have permission to view.
Missing permission checks in Jenkins 2.567 and earlier, LTS 2.555.2 and earlier allow attackers with Overall/Read permission to determine other users' configured timezone and to enumerate view names of other users' "My Views".
Jenkins 2.554 and earlier, LTS 2.541.2 and earlier does not safely handle symbolic links during the extraction of .tar and .tar.gz archives, allowing crafted archives to write files to arbitrary locations on the filesystem, restricted only by file system access permissions of the user running Jenkins.
This can be exploited to deploy malicious scripts or plugins on the controller by attackers with Item/Configure permission, or able to control agent processes.
Jenkins 2.550 and earlier, LTS 2.541.1 and earlier accepts Run Parameter values that refer to builds the user submitting the build does not have access to, allowing attackers with Item/Build and Item/Configure permission to obtain information about the existence of jobs, the existence of builds, and if a specified build exists, its display name.
A missing permission check in Jenkins 2.540 and earlier, LTS 2.528.2 and earlier allows attackers with View/Read permission to view encrypted password values in views.
Jenkins 2.540 and earlier, LTS 2.528.2 and earlier stores build authorization tokens unencrypted in job config.xml files on the Jenkins controller where they can be viewed by users with Item/Extended Read permission or access to the Jenkins controller file system.
Jenkins 2.540 and earlier, LTS 2.528.2 and earlier does not mask build authorization tokens displayed on the job configuration form, increasing the potential for attackers to observe and capture them.