CVE-2010-4020

CVE-2010-4020 describes a vulnerability in MIT Kerberos 5 versions 1.8.x through 1.8.3 where the system fails to reject RC4 key-derivation checksums. This flaw could allow remote authenticated attackers to forge AD-SIGNEDPATH or AD-KDC-ISSUED signatures, potentially leading to privilege escalation due to the small key space resulting from specific one-byte stream-cipher operations. The vulnerability has a CVSS v3 score of 6.3 (MEDIUM), indicating it can be exploited over a network with low complexity by a low-privileged user, resulting in low impact to confidentiality, integrity, and availability. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.