Remote heap overflow via extract_name
Published Dec 31, 2021 · Updated Aug 4, 2024
Heap-based buffer overflow in dnsmasq 2.86 allows remote attackers to compromise confidentiality, integrity, and availability via crafted DNS data. The rfc1035.c extract_name function writes up to MAXDNAME*2 bytes without accounting for offsets into the destination buffer, enabling an out-of-bounds heap write when called by answer_auth. The vendor disputes that CVE-2021-45951 through CVE-2021-45957 represent real vulnerabilities, so exploitation status remains contested.
Summary
What happened
Heap-based buffer overflow in dnsmasq 2.86 allows remote attackers to compromise confidentiality, integrity, and availability via crafted DNS data. The rfc1035.c extract_name function writes up to MAXDNAME*2 bytes without accounting for offsets into the destination buffer, enabling an out-of-bounds heap write when called by answer_auth. The vendor disputes that CVE-2021-45951 through CVE-2021-45957 represent real vulnerabilities, so exploitation status remains contested.
The record
- CVE
- CVE-2021-45954
- Published
- Dec 31, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 31, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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