CVE-2026-121506
HIGH
MEDIUM
Priority: 0.03
BB Relevance:
65/100
Published: 2026-11-03
Modified: 2026-11-03
First seen: 2026-11-03
Status: active
Attack Surface
Network
No Auth
No Interaction
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
None
UI:
None
S:
Unchanged
C:
None
I:
High
A:
High
Description
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.