NVD security advisoryHigh
High advisory for An out-of-bounds read and write in NTS c
CVE-2026-121506 · Reported 3 Nov 2026
Full advisory details, affected packages, severity context, and original source.
Affected technology
An out-of-bounds read and write in NTS cAffected product
Advisory overview
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.