CVE-2026-123573hickory-dns hickory-dns Improper Input Validation
NVD
Vulnerability Summary
hickory-dns from 0.20.1 before 0.26.2 contains a denial of service vulnerability in the hickory-proto SVCB and HTTPS record presentation format parser. Attackers can supply untrusted zone files where only a single or double quote replaces a service parameter value, triggering a panic that crashes the parsing process.
CVSS v4.0 Base Metrics — Score 8.7 (HIGH)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NAttack VectorNetwork
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionNone
Confidentiality (Vulnerable System)None
Integrity (Vulnerable System)None
Availability (Vulnerable System)High
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 7.5)
CVSS v3.1 Base Metrics — Score 7.5 (HIGH)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HAttack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
Affected & Patched Versions
- hickory-dns hickory-dns >= 0.20.1 and < 0.26.2
- hickory-dns hickory-dns 0.26.2
What to do
Plan remediation soon. No exploitation is confirmed yet, but the severity is high.
- Check whether you run hickory-dns hickory-dns and which version.
- Update to a patched version listed above, then confirm the new version.
Timeline
- Nov 8, 2026Published
- Nov 10, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
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Data last checked: Nov 14, 2026 02:13 UTC