CVE-2021-45951
highpriority · track · 40EPSS 0.027 · 86 %ileEURUUSEPSS · scored 2026-10-26
Dnsmasq 2.86 has a heap-based buffer overflow in check_bad_address (called from check_for_bogus_wildcard and FuzzCheckForBogusWildcard). 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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (6)
Products and version ranges known to be affected.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (13)
External citations — patches, advisories, analysis.
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35868cnnvd
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-924.yamlcnnvd
- https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.htmlcnnvd
- https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.htmlcnnvd
- https://vigilance.fr/vulnerability/Dnsmasq-buffer-overflow-via-check-bad-address-37158cnnvd
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35868enisa_euvd
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-924.yamlenisa_euvd
- https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.htmlenisa_euvd
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