CVE-2026-123584 (GCVE-0-2026-123584)

Vulnerability from cvelistv5 – Published: 2026-11-08 01:38 – Updated: 2026-11-08 01:38
VLAI
Title
Hickory-DNS 0.26.0 before 0.26.2 UDP Client Denial of Service via Spoofed Responses
Summary
The hickory-net crate in Hickory DNS 0.26.0 before 0.26.2 stops listening and returns an error when a client UDP connection receives a datagram that cannot be parsed as a DNS message. Remote attackers who guess the query's source port, without knowing the transaction ID, can spoof malformed responses to abort client queries, causing denial of service.
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-696 - Incorrect Behavior Order
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7770 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
hickory-dns hickory-dns Affected: 0.26.0 , < 0.26.2 (semver)
Unaffected: 0.26.2 (semver)
guessed Create a notification for this product.
Date Public
2026-09-03 00:00
Credits
qifan-sailboat
Show details on NVD website
To clipboard 

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}



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