NTP BUG 3042: Broadcast interleave

Last update: April 22, 2024 18:49 UTC (7e7bd5857)

---

Summary

Resolved	4.2.8p8	02 June 2016
References	Bug 3042	CVE-2016-4956
Affects	ntp-4, up to but not including ntp-4.2.8p8, and ntp-4.3.0 up to, but not including ntp-4.3.93.	Resolved in 4.2.8p8.
CVSS2 Score	LOW 2.6	AV:N/AC:H/Au:N/C:N/I:N/A:P
CVSS3 Score	LOW 3.7	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

---

Description

The fix for NTP Bug 2978 does not cover broadcast associations, so broadcast clients can be triggered to flip into interleave mode.

---

Mitigation

• Implement BCP-38.
• Upgrade to 4.2.8p8 or later.
• Properly monitor your ntpd instances.

---

Credit

This weakness was discovered by Miroslav Lichvar of Red Hat.

---

Timeline

• 2016 Jun 02: Public release
• 2016 May 24: Early Access Program Release: Premier and Partner Institutional Members
• : Notification to Institutional Members
• : Report received