Description
A vulnerability was found in dnsmasq before version 2.81, where the memory leak allows remote attackers to cause a denial of service (memory consumption) via vectors involving DHCP response creation.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The Dnsmasq Project | dnsmasq | before 2.81 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | dnsmasq | 2.81-1 | — |
| Debian 13 | dnsmasq | 2.81-1 | — |
| Debian 12 | dnsmasq | 2.81-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | dnsmasq | 2.80-1.1ubuntu1.2 | USN-4698-1 |
| Ubuntu 18.04 LTS | dnsmasq | 2.79-1ubuntu0.2 | USN-4698-1 |
| Ubuntu 16.04 LTS | dnsmasq | 2.75-1ubuntu0.16.04.7 | USN-4698-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | dnsmasq | 2.68-1ubuntu0.2+esm3 | USN-7689-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | dnsmasq +1 | 2.79-11.el8 | RHSA-2020:1715 |
| RHEL 7 | dnsmasq +1 | 2.76-16.el7 | RHSA-2020:3878 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | dnsmasq | 2.78-7.3.1 | SUSE-SU-2019:3189-1 |
| SLES 15 | dnsmasq | 2.78-3.8.1 | SUSE-SU-2019:3188-1 |
| SLES 12 SP5 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SLES 12 SP4 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SLES 11 SP4 | dnsmasq | 2.78-0.17.15.1 | SUSE-SU-2021:14603-1 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP5 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SLES for SAP 12 SP4 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE OpenStack Cloud Crowbar 9 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE OpenStack Cloud Crowbar 8 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE OpenStack Cloud 9 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE OpenStack Cloud 8 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE OpenStack Cloud 7 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
| SUSE HPE Helion OpenStack 8 | dnsmasq | 2.78-18.12.1 | SUSE-SU-2020:0419-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dnsmasq | 2.86-1.1 | openSUSE-SU-2024:10721-1 |
| openSUSE Leap 15.1 | dnsmasq | 2.78-lp151.5.3.1 | openSUSE-SU-2019:2669-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dnsmasq | 2.80-r5 | — |
| Alpine v3.23 | dnsmasq | 2.80-r5 | — |
| Alpine v3.22 | dnsmasq | 2.80-r5 | — |
| Alpine v3.21 | dnsmasq | 2.80-r5 | — |
| Alpine v3.20 | dnsmasq | 2.80-r5 | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | dnsmasq | 2.80-r5 | — |
| Alpine v3.18 | dnsmasq | 2.80-r5 | — |
| Alpine v3.17 | dnsmasq | 2.80-r5 | — |
| Alpine v3.16 | dnsmasq | 2.80-r5 | — |
| Alpine v3.15 | dnsmasq | 2.80-r5 | — |
| Alpine v3.14 | dnsmasq | 2.80-r5 | — |
| Alpine v3.13 | dnsmasq | 2.80-r5 | — |
| Alpine v3.12 | dnsmasq | 2.80-r5 | — |
| Alpine v3.11 | dnsmasq | 2.80-r5 | — |
| Alpine v3.10 | dnsmasq | 2.80-r4 | — |
| Alpine v3.9 | dnsmasq | 2.80-r4 | — |
| Alpine v3.8 | dnsmasq | 2.79-r4 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | dnsmasq +1 | 2.76-16.amzn2.0.1 | ALAS2-2020-1507 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | dnsmasq +1 | 2.79-11.el8 | ELSA-2020-1715 |
| Oracle Linux 7 | dnsmasq +1 | 2.76-16.el7 | ELSA-2020-3878 |
Advisories 14
- RHSA-2020:3878 Red Hat Security Advisory: dnsmasq security and bug fix update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- USN-7689-1 dnsmasq vulnerability Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-4698-1 dnsmasq vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2019:3188-1 Security update for dnsmasq SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3189-1 Security update for dnsmasq SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10721-1 dnsmasq-2.86-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:14603-1 Security update for dnsmasq SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0419-1 Security update for dnsmasq SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2669-1 Security update for dnsmasq SUSE / openSUSE Security Updates · Feb 4, 2026
- RHSA-2020:1715 Red Hat Security Advisory: dnsmasq security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- WID-SEC-2023-0719 dnsmasq: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Aug 11, 2025
- ALAS2-2020-1507 Low: dnsmasq security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Oct 22, 2020
- ELSA-2020-3878 Low: dnsmasq security and bug fix update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 6, 2020
- ELSA-2020-1715 Low: dnsmasq security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 5, 2020