CVE-2026-121506: high-severity vulnerability in NTPsec
Out-of-bounds Write in NTPsec
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.4epss 0.4%
An out-of-bounds read and write in NTS client extension field parsing (extens_client_recv) in NTPsec before 1.2.5 allows a remote attacker who can send NTP server-mode replies to an NTS client to corrupt heap memory and crash ntpd, and, combined with the NTS-KE client out-of-bounds read fixed in 1.2.4, to bypass NTS authentication and set the client's time, via an NTS Authenticator and Encrypted Extension Fields field whose nonce length exceeds the field.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
Affected products
NTPsec · NTPsecRelated CVEs — NTPsec
In the same product, most dangerous first.