Description
A flaw was found in dnsmasq. When DHCP leasequery is enabled without listing allowed source addresses, the server does not check who sent the query. A host on the local network can request DHCP lease records and learn assigned addresses, MAC addresses, hostnames, and related lease metadata. The feature is off unless an administrator turns it on.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat Ceph Storage 9 | — | — |
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 5 | — | — |
| Red Hat | Red Hat OpenStack Platform 13 (Queens) | — | — |
| Red Hat | Red Hat OpenStack Platform 18.0 | — | — |
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 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | dnsmasq | No fix yet | — |
| Ubuntu 26.04 LTS | dnsmasq | No fix yet | — |
| Ubuntu 24.04 LTS | dnsmasq | No fix yet | — |
| Ubuntu 22.04 LTS | dnsmasq | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | dnsmasq | No fix yet | — |
| Ubuntu Pro 18.04 LTS | dnsmasq | No fix yet | — |
| Ubuntu Pro 16.04 LTS | dnsmasq | No fix yet | — |
| Ubuntu Pro 14.04 LTS | dnsmasq | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | dnsmasq | No fix yet | — |
Advisories 1
- WID-SEC-2026-4256 dnsmasq: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 29, 2026
References
- https://access.redhat.com/security/cve/CVE-2026-93010 vdb-entry
- RHBZ#2536081 issue-tracking