ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-1548.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2016-4956 from the MITRE CVE dictionary dictionary and NIST NVD.
NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.
| Base Score | 2.6 |
|---|---|
| Base Metrics | AV:N/AC:H/Au:N/C:N/I:N/A:P |
| Access Vector | Network |
| Access Complexity | High |
| Authentication | None |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | Partial |
Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise Linux 7 | ntp | Fix deferred |
| Red Hat Enterprise Linux 6 | ntp | Fix deferred |
| Red Hat Enterprise Linux 5 | ntp | Will not fix |
Do not use NTP's broadcast mode in the clients by not configuring the "broadcastclient" directive in the ntp.conf file.
Vulmon