# CVE-2020-37127: dnsmasq: Dnsmasq-utils 2.79-1 contains a buffer overflow vulnerability in the dhcp_release utility that allows attackers to ca...

CVE-2020-37127 is fixed in 4 products on 1 platform, first by dnsmasq 2.90-0ubuntu0.18.04.1+esm1, released January 16, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-37127
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0021
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 5, 2026

## Description

Dnsmasq-utils 2.79-1 contains a buffer overflow vulnerability in the dhcp_release utility that allows attackers to cause a denial of service by supplying excessive input. Attackers can trigger a core dump and terminate the dhcp_release process by sending a crafted input string longer than 16 characters.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dnsmasq Debian 12.15 (bookworm) | 2.80-1 | [DEBIAN-CVE-2020-37127](https://patchblox.com/security/data/fix/linux/debian-cve-2020-37127.md) | Feb 5, 2026 |
| Linux | dnsmasq Debian 13.5 (trixie) | 2.80-1 | [DEBIAN-CVE-2020-37127](https://patchblox.com/security/data/fix/linux/debian-cve-2020-37127.md) | Feb 5, 2026 |
| Linux | dnsmasq Debian 14 | 2.80-1 | [DEBIAN-CVE-2020-37127](https://patchblox.com/security/data/fix/linux/debian-cve-2020-37127.md) | Feb 5, 2026 |
| Linux | dnsmasq Ubuntu 18.04.6 LTS (bionic) | 2.90-0ubuntu0.18.04.1+esm1 | [dnsmasq 2.90-0ubuntu0.18.04.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-dnsmasq-2.90-0ubuntu0.18.04.1-esm1.md) | Jan 16, 2026 |
| Linux | dnsmasq Ubuntu 22.04.1 LTS (jammy) | 2.90-0ubuntu0.22.04.1 | [dnsmasq 2.90-0ubuntu0.22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-dnsmasq-2.90-0ubuntu0.22.04.1.md) | Jan 16, 2026 |
| Linux | dnsmasq-base Ubuntu 18.04.6 LTS (bionic) | 2.90-0ubuntu0.18.04.1+esm1 | [dnsmasq-base 2.90-0ubuntu0.18.04.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-dnsmasq-base-2.90-0ubuntu0.18.04.1-esm1.md) | Jan 16, 2026 |
| Linux | dnsmasq-base Ubuntu 22.04.1 LTS (jammy) | 2.90-0ubuntu0.22.04.1 | [dnsmasq-base 2.90-0ubuntu0.22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-dnsmasq-base-2.90-0ubuntu0.22.04.1.md) | Jan 16, 2026 |
| Linux | dnsmasq-base-lua Ubuntu 18.04.6 LTS (bionic) | 2.90-0ubuntu0.18.04.1+esm1 | [dnsmasq-base-lua 2.90-0ubuntu0.18.04.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-dnsmasq-base-lua-2.90-0ubuntu0.18.04.1-esm1.md) | Jan 16, 2026 |
| Linux | dnsmasq-base-lua Ubuntu 22.04.1 LTS (jammy) | 2.90-0ubuntu0.22.04.1 | [dnsmasq-base-lua 2.90-0ubuntu0.22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-dnsmasq-base-lua-2.90-0ubuntu0.22.04.1.md) | Jan 16, 2026 |
| Linux | dnsmasq-utils Ubuntu 18.04.6 LTS (bionic) | 2.90-0ubuntu0.18.04.1+esm1 | [dnsmasq-utils 2.90-0ubuntu0.18.04.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-dnsmasq-utils-2.90-0ubuntu0.18.04.1-esm1.md) | Jan 16, 2026 |
| Linux | dnsmasq-utils Ubuntu 22.04.1 LTS (jammy) | 2.90-0ubuntu0.22.04.1 | [dnsmasq-utils 2.90-0ubuntu0.22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-dnsmasq-utils-2.90-0ubuntu0.22.04.1.md) | Jan 16, 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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