Rule Category

SERVER-OTHER -- Snort has detected traffic exploiting vulnerabilities in a server in the network.

Alert Message

SERVER-OTHER MIT Kerberos 5 krb5_read_message klogin ksh kprop protocols bad app version string denial of service attempt

Rule Explanation

This event is generated when malformed kerberos message triggers denial of service in krb5_read_message in MIT Kerberos 5. Impact: Attempted Denial of Service Details: Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Rule Vulnerability

CVE Additional Information

CVE-2014-5355
MIT Kerberos 5 (aka krb5) through 1.13.1 incorrectly expects that a krb5_read_message data field is represented as a string ending with a '\0' character, which allows remote attackers to (1) cause a denial of service (NULL pointer dereference) via a zero-byte version string or (2) cause a denial of service (out-of-bounds read) by omitting the '\0' character, related to appl/user_user/server.c and lib/krb5/krb/recvauth.c.
Details
SeverityMEDIUM Base Score5.0
Impact Score2.9 Exploit Score10.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access