Description
Heap-based buffer overflow in the JJY refclock driver in NTPsec ntpd before 1.2.6 allows an attacker who controls the Telephone JJY time source to corrupt memory or crash ntpd via more than six time replies.
References2
Metrics
- CVSS 3.1
-
6.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H - EPSS — exploit probability
- 0% percentile: 11 · as of 8 November 2026
- CWE
- CWE-122
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.