CVE-2026-4890

Publication date 11 May 2026

Last updated 13 May 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
dnsmasq 26.04 LTS resolute
Fixed 2.92-1ubuntu0.2
25.10 questing
Fixed 2.91-1ubuntu0.2
24.04 LTS noble
Fixed 2.90-2ubuntu0.3
22.04 LTS jammy
Fixed 2.90-0ubuntu0.22.04.3
20.04 LTS focal
Fixed 2.90-0ubuntu0.20.04.1+esm2
18.04 LTS bionic
Fixed 2.90-0ubuntu0.18.04.1+esm3
16.04 LTS xenial
Fixed 2.90-0ubuntu0.16.04.1+esm3
14.04 LTS trusty
Not affected

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro 30-day free trial

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

Other references

Access our resources on patching vulnerabilities