CVE-2026-4893

An information disclosure vulnerability in dnsmasq allows remote attackers to bypass source checks via a crafted DNS packet with RFC 7871 client subnet information.

Score

CVSS 3.1 5.3 Medium

Status

Awaiting Analysis - cret@cert.org

Published

2026-05-11

Last modified

2026-05-20

Affected products

• Dnsmasq (Dnsmasq)

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