A Denial of Service (DoS) vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet.
Weakness
The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | RedHat | dnsmasq-0:2.90-7.el10_2 | * |
| Red Hat Enterprise Linux 8 | RedHat | dnsmasq-0:2.79-36.el8_10 | * |
| Red Hat Enterprise Linux 9 | RedHat | dnsmasq-0:2.85-18.el9_8.1 | * |
| Red Hat Enterprise Linux 9.6 Extended Update Support | RedHat | dnsmasq-0:2.85-17.el9_6.1 | * |
| Dnsmasq | Ubuntu | devel | * |
| Dnsmasq | Ubuntu | esm-infra-legacy/xenial | * |
| Dnsmasq | Ubuntu | esm-infra/bionic | * |
| Dnsmasq | Ubuntu | esm-infra/focal | * |
| Dnsmasq | Ubuntu | esm-infra/xenial | * |
| Dnsmasq | Ubuntu | jammy | * |
| Dnsmasq | Ubuntu | noble | * |
| Dnsmasq | Ubuntu | questing | * |
| Dnsmasq | Ubuntu | resolute | * |
References
- https://github.com/NixOS/nixpkgs/pull/519082
- https://github.com/NixOS/nixpkgs/pull/519093
- https://github.com/pi-hole/FTL/releases/tag/v6.6.2
- https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html
- https://thekelleys.org.uk/dnsmasq/CVE/
- https://www.kb.cert.org/vuls/id/471747
- https://access.redhat.com/errata/RHSA-2026:19158
- https://access.redhat.com/errata/RHSA-2026:19373
- https://access.redhat.com/errata/RHSA-2026:20589
- https://access.redhat.com/errata/RHSA-2026:34508
- https://access.redhat.com/security/cve/CVE-2026-4890
- https://bugzilla.redhat.com/show_bug.cgi?id=2458516
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4890.json