Ubuntu Security Notice 5828-1 - It was discovered that Kerberos incorrectly handled certain S4U2Self requests. An attacker could possibly use this issue to cause a denial of service. This issue was only addressed in Ubuntu 16.04 ESM and Ubuntu 18.04 LTS. Greg Hudson discovered that Kerberos PAC implementation incorrectly handled certain parsing operations. A remote attacker could use this issue to cause a denial of service, or possibly execute arbitrary code.
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