CVE-2021-45955

Public Exploit

Description

Dnsmasq 2.86 has a heap-based buffer overflow in resize_packet (called from FuzzResizePacket and fuzz_rfc1035.c) because of the lack of a proper bounds check upon pseudo header re-insertion. 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." However, a contributor states that a security patch (mentioned in 016162.html) is needed

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.04%
Third-Party Advisory chromium.org Third-Party Advisory github.com Third-Party Advisory org.uk Third-Party Advisory org.uk
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-932.yaml third party advisory
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35898 issue tracking exploit third party advisory
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html third party advisory mailing list
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-45955?
CVE-2021-45955 has been scored as a critical severity vulnerability.
How to fix CVE-2021-45955?
To fix CVE-2021-45955, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-45955 being actively exploited in the wild?
It is possible that CVE-2021-45955 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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