CVE-2026-2966
Cesanta Mongoose DNS Transaction ID dns.c mg_sendnsreq random values
Description
A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
INFO
Published Date :
Feb. 23, 2026, 3:15 a.m.
Last Modified :
Feb. 23, 2026, 8:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 2.0 | LOW | [email protected] | ||||
| CVSS 3.1 | LOW | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update Cesanta Mongoose to version 7.21 or later.
- Apply vendor patches if available.
- Review DNS transaction ID generation.
- Monitor for related security advisories.
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-2026-2966.
| URL | Resource |
|---|---|
| https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md | Exploit Third Party Advisory |
| https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md#poc | Exploit Third Party Advisory |
| https://vuldb.com/?ctiid.347333 | Permissions Required VDB Entry |
| https://vuldb.com/?id.347333 | Third Party Advisory VDB Entry |
| https://vuldb.com/?submit.755304 | Third Party Advisory VDB Entry |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-2966 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-2026-2966
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-2026-2966 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-2966 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.
-
Initial Analysis by [email protected]
Feb. 23, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:* versions up to (including) 7.20 Added Reference Type VulDB: https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md Types: Exploit, Third Party Advisory Added Reference Type VulDB: https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md#poc Types: Exploit, Third Party Advisory Added Reference Type VulDB: https://vuldb.com/?ctiid.347333 Types: Permissions Required, VDB Entry Added Reference Type VulDB: https://vuldb.com/?id.347333 Types: Third Party Advisory, VDB Entry Added Reference Type VulDB: https://vuldb.com/?submit.755304 Types: Third Party Advisory, VDB Entry -
New CVE Received by [email protected]
Feb. 23, 2026
Action Type Old Value New Value Added Description A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way. Added CVSS V4.0 AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N Added CVSS V2 (AV:N/AC:H/Au:N/C:N/I:P/A:N) Added CWE CWE-310 Added CWE CWE-330 Added Reference https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md Added Reference https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md#poc Added Reference https://vuldb.com/?ctiid.347333 Added Reference https://vuldb.com/?id.347333 Added Reference https://vuldb.com/?submit.755304