# CVE-2026-2966: swupdate: A weakness has been identified in Cesanta Mongoose up to 7.20

CVE-2026-2966 is fixed in swupdate on 1 platform by DEBIAN-CVE-2026-2966 (version 2025.12+dfsg-10), released February 23, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-2966
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0044
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 23, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | swupdate Debian 14 | 2025.12+dfsg-10 | [DEBIAN-CVE-2026-2966](https://patchblox.com/security/data/fix/linux/debian-cve-2026-2966.md) | Feb 23, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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