CVE-2026-123571
Received
Received - Intake
Integer Underflow in TSIG RDATA Decoding in Hickory DNS
Vulnerability report for CVE-2026-123571, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-08
Last updated on: 2026-11-08
Assigner: VulnCheck
Description
Description
Hickory DNS from 0.26.0 before 0.26.2 contains an integer underflow vulnerability in TSIG RDATA decoding that allows remote attackers to trigger a panic via malformed records. Attackers can send a crafted TSIG record in DNS wire format to cause unchecked subtraction underflow, crashing builds with overflow checks enabled and causing denial of service.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| hickory_dns | hickory_dns | to 0.26.2 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-191 | The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. |