The remote API in Jenkins 2.73.1 and earlier, 2.83 and earlier at /computer/(agent-name)/api showed information about tasks (typically builds) currently running on that agent. This included information about tasks that the current user otherwise has no access to, e.g. due to lack of Item/Read permission. This has been fixed, and the API now only shows information about accessible tasks.
github.com/jenkinsci/jenkins
github.com/jenkinsci/jenkins/blob/e27b310065b3c036b5fc9d123f1d1d99d3058c00/test/src/test/java/hudson/model/ExecutorTest.java
github.com/jenkinsci/jenkins/commit/da06fd471cea79123821c778228eeb08e1cedcc7
jenkins.io/security/advisory/2017-10-11
nvd.nist.gov/vuln/detail/CVE-2017-1000398