An out-of-bounds read and write in NTS client extension field parsing (extensclientrecv) in NTPsec before 1.2.5 allows a remote attacker…
CVE-2026-121506
An out-of-bounds read and write in NTS client extension field parsing (extensclientrecv) 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.
Assessment
- CVSS
- 7.4 (v3.1)
- Severity
- High
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 3 November 2026
- Last updated
- 3 November 2026
- Assigner
- GitLab
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
At the source
References
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