{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-123604", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-11-06T01:00:16.506Z", "datePublished": "2026-11-08T01:38:31.351Z", "dateUpdated": "2026-11-08T01:38:31.351Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-11-08T01:38:31.351Z"}, "datePublic": "2026-09-03T00:00:00.000Z", "title": "Hickory DNS 0.26.0-beta.1 before 0.26.2 Resource Exhaustion DoS via NameServerPool::try_send TC-Retry Loop", "descriptions": [{"lang": "en", "value": "Hickory DNS hickory-resolver 0.26.0-beta.1 before 0.26.2 contains an unbounded retry loop in NameServerPool::try_send, which re-queues truncated (TC) responses without checking the answering transport or counting iterations. A malicious authoritative server returning TC=1 on every transport keeps the resolver spinning on a persistent TCP connection until the 5-second request deadline expires, causing resource exhaustion."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Loop with Unreachable Exit Condition ('Infinite Loop')", "cweId": "CWE-835", "type": "CWE"}]}], "affected": [{"vendor": "hickory-dns", "product": "hickory-dns", "defaultStatus": "unaffected", "packageURL": "pkg:cargo/hickory-resolver", "versions": [{"version": "0.26.0-beta.1", "status": "affected", "versionType": "semver", "lessThan": "0.26.2"}, {"version": "0.26.2", "status": "unaffected", "versionType": "semver"}]}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "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", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS"}, {"cvssV3_1": {"attackComplexity": "LOW", "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"}], "references": [{"url": "https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-6w6g-hm98-mhgm", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-6w6g-hm98-mhgm)"}, {"name": "VulnCheck Advisory: Hickory DNS 0.26.0-beta.1 before 0.26.2 Resource Exhaustion DoS via NameServerPool::try_send TC-Retry Loop", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/hickory-dns-0.26.0-beta.1-before-0.26.2-resource-exhaustion-dos-via-nameserverpool-try-send-tc-retry-loop"}], "credits": [{"lang": "en", "value": "qifan-sailboat", "type": "reporter"}], "x_generator": {"engine": "vulncheck-endgame"}}}}