[org.jenkins-ci.main:jenkins-core] Improper Input Validation in Jenkins

Jenkins 2.286 and earlier, LTS 2.277.1 and earlier does not validate the type of object created after loading the data submitted to the config.xml REST API endpoint of a node, allowing attackers with Computer/Configure permission to replace a node with one of a different type.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-21639
• https://www.jenkins.io/security/advisory/2021-04-07/#SECURITY-1721
• http://www.openwall.com/lists/oss-security/2021/04/07/2
• https://github.com/advisories/GHSA-pvwx-3jx5-24r2