CVE-2018-1000863: A data modification vulnerability exists in Jenkins 2.153 and earlier, LTS 2.138.3 and earlier in User.java...

Security readout for executives and security teams

Older Jenkins releases can mishandle specially crafted user names during user record storage migration. The reported impact is that a victim may be unable to log into Jenkins. This is mainly an availability and account-access risk, not evidence of code execution or data theft in the provided sources. Exposure is most likely where affected Jenkins controllers allow user creation, authentication flows, or submitted user names from untrusted or less-trusted users. Publicly reachable Jenkins instances and shared CI environments have higher operational risk. Treat this as a moderate operational risk. It can interfere with Jenkins access and disrupt delivery pipelines, especially if administrator or service accounts are affected, but the provided sources do not indicate active exploitation or remote code execution. Mitigation focus: Identify Jenkins controllers at version 2.153 or earlier, including LTS 2.138.3 or earlier.; Follow Jenkins SECURITY-1072 vendor guidance for fixed releases or supported upgrade paths.; Restrict Jenkins access to trusted networks while remediation is planned..

Prepared

Jun 6, 2026, 22:09 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.