CVE-2026-123586
📛 CVE Title
Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals
Description
Hickory DNS 0.25.0-alpha.3 through 0.25.2 contains a query amplification vulnerability in its recursive resolver, which mishandles cyclic sibling name server referrals that lack glue records. Attackers controlling two zones whose name servers reference each other without glue records can make the recursor loop, sending many upstream queries, amplified further by zero-TTL NS records.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- VulnCheck
- CVSS severity
- HIGH
- CVSS score
- 8.7 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N- Effective score
- 8.7 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-400 - Reserved
- 2026-11-06
- Published
- 2026-11-08 01:38 UTC
- Last updated
- 2026-11-08 01:38 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/123xxx/CVE-2026-123586.json
- Linked Threat
- CVE-2026-123586 — Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-119345
EUVD enrichment is queued; refresh the page in a few seconds.
Affected products (2)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| hickory-dns | hickory-dns |
0.25.0-alpha.3 (affected)
|
— |
| hickory-dns | hickory-dns |
0 (affected),
0.26.2 (unaffected)
|
— |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- GitHub Security Advisory (GHSA-cx5j-p54p-q756) vendor-advisory
- VulnCheck Advisory: Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals third-party-advisory
MITRE references (2) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
- GitHub Security Advisory (GHSA-cx5j-p54p-q756) vendor-advisory
- VulnCheck Advisory: Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals third-party-advisory
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
Remediations (10)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blogs.oracle.com
For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-11-08 10:22 UTC -
web:cyberupdates365.com
Track critical CVE vulnerabilities 2026 with verified enterprise patch guides. Fix zero-days across VMware, WordPress, Windows, and cloud infrastructure.
2026-11-08 10:22 UTC -
web:cycode.com
Learn about sshole ( CVE - 2026 -123158), an OpenSSH authentication bypass vulnerability affecting Alpine Linux, key exposure criteria, affected public images, and fix guidance.
2026-11-08 10:22 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-11-08 10:22 UTC -
web:support.sap.com
On 13 th of October 2026 , SAP security patch day saw the release of 16 new security notes and 4 GitHub security advisories. There are 2 updates to previously released security notes.
2026-11-08 10:22 UTC -
web:support.servicenow.com
What you need to know: On September 24, 2026 , ServiceNow issued CVE - 2026 -86857, CVE - 2026 -86858, CVE - 2026 -13016, CVE - 2026 -86859, and CVE - 2026 -86860. Each of these security issues was identified through internal security testing, customer security assessments, or reports submitted through ServiceNow's responsible disclosure and bug bounty programs and was remediated independently. For security ...
2026-11-08 10:22 UTC -
web:www.aikido.dev
CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.
2026-11-08 10:22 UTC -
web:www.openhands.dev
Compare 8 automated vulnerability remediation tools for 2026 on fixes, prioritization, integrations, and deployment control.
2026-11-08 10:22 UTC -
web:www.oracle.com
This Critical Patch Update contains 1295 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at October 2026 Critical Patch Update: Executive Summary and Analysis.
2026-11-08 10:22 UTC -
web:www.oracle.com
Prior Critical Patch Update and Critical Security Patch Update advisories should be reviewed for information regarding earlier published security patches. Refer to Critical Patch Updates, Critical Security Patch Updates, Security Alerts and Bulletins for information about Oracle Security advisories.
2026-11-08 10:22 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-123586.json.
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"packageURL": "pkg:cargo/hickory-recursor",
"product": "hickory-dns",
"vendor": "hickory-dns",
"versions": [
{
"lessThanOrEqual": "0.25.2",
"status": "affected",
"version": "0.25.0-alpha.3",
"versionType": "semver"
}
]
},
{
"defaultStatus": "unaffected",
"packageURL": "pkg:cargo/hickory-resolver",
"product": "hickory-dns",
"vendor": "hickory-dns",
"versions": [
{
"lessThan": "0.26.2",
"status": "affected",
"version": "0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "0.26.2",
"versionType": "semver"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "qifan-sailboat"
}
],
"datePublic": "2026-09-03T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Hickory DNS 0.25.0-alpha.3 through 0.25.2 contains a query amplification vulnerability in its recursive resolver, which mishandles cyclic sibling name server referrals that lack glue records. Attackers controlling two zones whose name servers reference each other without glue records can make the recursor loop, sending many upstream queries, amplified further by zero-TTL NS records."
}
],
"metrics": [
{
"cvssV4_0": {
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"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "NETWORK",
"baseScore": 8.7,
"baseSeverity": "HIGH",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
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"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS"
},
{
"cvssV3_1": {
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"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-400",
"description": "Uncontrolled Resource Consumption",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-11-08T01:38:18.937Z",
"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"shortName": "VulnCheck"
},
"references": [
{
"name": "GitHub Security Advisory (GHSA-cx5j-p54p-q756)",
"tags": [
"vendor-advisory"
],
"url": "https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-cx5j-p54p-q756"
},
{
"name": "VulnCheck Advisory: Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals",
"tags": [
"third-party-advisory"
],
"url": "https://www.vulncheck.com/advisories/hickory-dns-0.25.0-alpha.3-through-0.25.2-query-amplification-via-cyclic-referrals"
}
],
"title": "Hickory DNS 0.25.0-alpha.3 through 0.25.2 Query Amplification via Cyclic Referrals",
"x_generator": {
"engine": "vulncheck-endgame"
}
}
},
"cveMetadata": {
"assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"assignerShortName": "VulnCheck",
"cveId": "CVE-2026-123586",
"datePublished": "2026-11-08T01:38:18.937Z",
"dateReserved": "2026-11-06T00:57:31.044Z",
"dateUpdated": "2026-11-08T01:38:18.937Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}