NTP BUG 3102: Zero Origin timestamp regression

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

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Summary

Resolved	4.2.8p9	21 Nov 2016
References	Bug 3102	CVE-2016-7431
Affects	ntp-4.2.8p8 and ntp-4.3.93.	Resolved in 4.2.8p9.
CVSS2 Score	MED 5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N
CVSS3 Score	MED 5.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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Description

Zero Origin timestamp problems were fixed by Bug 2945 in ntp-4.2.8p6. However, subsequent timestamp validation checks introduced a regression in the handling of some Zero origin timestamp checks.

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Mitigation

• Implement BCP-38.
• Upgrade to 4.2.8p9 or later.
• Properly monitor your ntpd instances, and auto-restart ntpd (without -g) if it stops running.

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Credit

This weakness was discovered by Sharon Goldberg and Aanchal Malhotra of Boston University.

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Timeline

• 2016 Nov 21: Public release
• 2016 Nov 15: CERT given our software release notification
• 2016 Nov 14: Early Access Program Release: Premier and Partner Institutional Members
• : Notification to Institutional Members
• : Report received