CVE-2023-28450

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-03-15 · updated 2026-06-17

Description

An issue was discovered in Dnsmasq before 2.90. The default maximum EDNS.0 UDP packet size was set to 4096 but should be 1232 because of DNS Flag Day 2020.

Affected products

Simon Kelley dnsmasq: before 2.90 — fixed in 2.90

How to fix

Upgrade to a fixed version: Simon Kelley dnsmasq 2.90. Check the vendor advisory for mitigations.

References

https://capec.mitre.org/data/definitions/495.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6UQ6LKDTLSSD64TBIZ3XEKBM2SWC63VV/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OU2ZT4ITSEOOR2CFBAHK4Z67KXJIEWQA/
https://thekelleys.org.uk/dnsmasq/doc.html
https://thekelleys.org.uk/gitweb/?p=dnsmasq.git%3Ba=blob%3Bf=CHANGELOG
https://thekelleys.org.uk/gitweb/?p=dnsmasq.git%3Ba=commit%3Bh=eb92fb32b746f2104b0f370b5b295bb8dd4bd5e5
https://capec.mitre.org/data/definitions/495.html
https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6UQ6LKDTLSSD64TBIZ3XEKBM2SWC63VV/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OU2ZT4ITSEOOR2CFBAHK4Z67KXJIEWQA/
https://thekelleys.org.uk/dnsmasq/doc.html
https://thekelleys.org.uk/gitweb/?p=dnsmasq.git%3Ba=blob%3Bf=CHANGELOG

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