CVE-2026-121505
Out-of-bounds Read in NTPsec
Description
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.
INFO
Published Date :
Nov. 3, 2026, 3:17 p.m.
Last Modified :
Nov. 3, 2026, 4:15 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-121505
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | LOW | ceab7361-8a18-47b1-92ba-4d7d25f6715a | ||||
| CVSS 3.1 | LOW | [email protected] |
Solution
- Update NTPsec to version 1.2.4 or later.
- Apply vendor patches if available.
- Validate server configurations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-121505.
| URL | Resource |
|---|---|
| https://gitlab.com/NTPsec/ntpsec/-/commit/caf0eb5df3c6ddbfc2941389bff0f9146835c021 | |
| https://gitlab.com/NTPsec/ntpsec/-/work_items/836 | |
| https://gitlab.com/NTPsec/ntpsec/-/work_items/902 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-121505 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-121505
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-121505 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-121505 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 03, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N Added CWE CWE-125 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/121xxx/CVE-2026-121505.json">CVE-2026-121505</a> Added Reference https://gitlab.com/NTPsec/ntpsec/-/commit/caf0eb5df3c6ddbfc2941389bff0f9146835c021 Added Reference https://gitlab.com/NTPsec/ntpsec/-/work_items/836 Added Reference https://gitlab.com/NTPsec/ntpsec/-/work_items/902