What is CVE-2026-121505?

CVE-2026-121505 is a low-severity vulnerability in Ntpsec, classified under Out-of-bounds Read. CVSS score: 3.7/10. Published 2026-11-03.

How severe is CVE-2026-121505?

Low severity. CVSS v3 base score is 3.7 out of 10.

Out-of-bounds Read in Ntpsec

CVE-2026-121505

An out-of-bounds read in the NTS-KE client response parser (nts_client_process_response_core) in NTPsec before 1.2.4 allows a malicious NTS-KE server to read the client's stack memory, including pointers that defeat ASLR, which the client then sends in cleartext as NTS cookies, via an NTS-KE record whose declared length exceeds the data received.

Vulnerability class: Buffer Overflow

Published 2026-11-03 · last modified 2026-11-03.

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Ntpsec

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

Frequently asked questions

What is CVE-2026-121505?: CVE-2026-121505 is a low-severity vulnerability in Ntpsec, classified under Out-of-bounds Read. CVSS score: 3.7/10. Published 2026-11-03.
How severe is CVE-2026-121505?: Low severity. CVSS v3 base score is 3.7 out of 10.