CVE-2016-3120
CWE-476Published: August 1, 2016· Updated: Jun 17, 2026
Official Description
The validate_as_request function in kdc_util.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.13.6 and 1.4.x before 1.14.3, when restrict_anonymous_to_tgt is enabled, uses an incorrect client data structure, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an S4U2Self request.
Technical Analysis
CVE-2016-3120 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (20)
Quick Facts
Related CVEs (CWE-476)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2016-3120 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts