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CVE Record

CVE-2021-45953: Dnsmasq 2.86 has a heap-based buffer overflow in extract_name (called from hash_questions and fuzz_util.c).

Dnsmasq 2.86 has a heap-based buffer overflow in extract_name (called from hash_questions and fuzz_util.c). 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.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

This CVE reports a heap-based buffer overflow in dnsmasq 2.86, but the available record lacks severity, CVSS, and confirmed affected-product metadata. The vendor publicly stated that this CVE group does not represent real vulnerabilities to the best of their knowledge, so business urgency is uncertain.

Executive priority

Track and validate, but do not escalate as confirmed high risk from these sources alone. Prioritize only if dnsmasq 2.86 is present in important systems or a trusted vendor later confirms exploitability or a fix.

Technical view

The report names extract_name in dnsmasq 2.86, called from hash_questions and fuzz_util.c, as the overflow location. The evidence appears tied to OSS-Fuzz reporting. No CVSS vector, CWE, supported exploitability assessment, or vendor patch information is included in the supplied sources.

Likely exposure

Exposure is only source-supported for environments running dnsmasq 2.86. The CVE record lists affected vendor and product as n/a, so downstream distributions, embedded use, and appliance impact are not confirmed by the supplied bundle.

Exploitation context

The source bundle does not show active exploitation, and the CVE is not in KEV. Vendor discussion disputes whether this CVE group represents real vulnerabilities, so treat exploitability as unproven unless additional vendor or distribution evidence emerges.

Researcher notes

Key gaps are missing CVSS, absent CWE mapping, n/a affected metadata, and vendor disagreement. Further analysis should distinguish fuzzer-discovered memory safety behavior from a reachable production attack path without publishing exploit guidance.

Mitigation direction

  • Inventory systems running dnsmasq 2.86.
  • Check dnsmasq and distribution vendor guidance for this specific CVE.
  • Apply vendor-supported package updates if your distribution ships a fix.
  • Avoid assuming exposure for products not named by vendor sources.

Validation and detection

  • Confirm deployed dnsmasq versions from asset inventory or package data.
  • Review the referenced OSS-Fuzz issue and OSV entry for scope details.
  • Check vendor mailing-list statements before assigning remediation urgency.
  • Document whether dnsmasq is present and business-critical in each environment.
Prepared
Confidence
medium
Sources
6

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2021-45953 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
5Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.