CVE-2021-45956

dnsmasq: a heap-based buffer overflow in print_mac

Published 1 Jan 2022Modified 17 Jun 2026CWE 787

In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.

Severity by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Trivy's own label is CRITICAL. Rated critical by NVD, CBL-Mariner.

Description

Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge.

Affected packages and fixed versions

Source	Package	Fixed in
CBL-Mariner 2.0	dnsmasq	0:2.89-1.cm2

References

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