Shawn Emery

**Name of the Vulnerable Software and Affected Versions** MIT Kerberos 5 (aka krb5) versions 1.7.x through 1.8.1 MIT Kerberos 5 (aka krb5) versions prior to 1.9.2 **Description** A double free vulnerability exists in the Key Distribution Center (KDC) in MIT Kerberos 5, which can be exploited by remote authenticated users. This issue is associated with requests for renewal or validation and can cause a denial of service (daemon crash) or possibly allow the execution of arbitrary code. Multiple vulnerabilities in the mit-krb5 package can lead to breaches of confidentiality, integrity, and availability of protected information, and these vulnerabilities can be exploited remotely. **Recommendations** For versions 1.7.x through 1.8.1, update to version 1.8.2 or later to resolve the issue. For versions prior to 1.9.2, update to version 1.9.2 or later to resolve the issue. As a temporary workaround, consider restricting access to the Key Distribution Center (KDC) to minimize the risk of exploitation.

**Name of the Vulnerable Software and Affected Versions** MIT Kerberos 5 versions prior to 1.8.2 mit-krb5 versions prior to 1.9.2-r1 **Description** The issue is related to multiple vulnerabilities in the MIT Kerberos 5 package, which can lead to a denial of service (NULL pointer dereference and daemon crash) via an AP-REQ message in which the authenticator's checksum field is missing. The kg accept krb5 function in krb5/accept sec context.c does not properly check for invalid GSS-API tokens. The vulnerabilities can be exploited remotely. **Recommendations** For MIT Kerberos 5 versions prior to 1.8.2, update to version 1.8.2 or later. For mit-krb5 versions prior to 1.9.2-r1, update to version 1.9.2-r1 or later. As a temporary workaround, consider disabling the kg accept krb5 function until a patch is available. Restrict access to the GSS-API library to minimize the risk of exploitation. Avoid using the AP-REQ message with missing authenticator's checksum field in the affected API endpoint until the issue is resolved.