CVE-2026-33261

A zone transition from NSEC to NSEC3 might trigger an internal inconsistency and cause a denial of service.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-03.html	Broken Link Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:powerdns:recursor::::::::
	cpe:2.3:a:powerdns:recursor::::::::
	cpe:2.3:a:powerdns:recursor:5.4.0:::::::*

History

No history.

Information

Published : 2026-04-22 10:16

Updated : 2026-06-17 10:37

NVD link : CVE-2026-33261

Mitre link : CVE-2026-33261

CVE.ORG link : CVE-2026-33261

JSON object : View

Products Affected

powerdns

recursor

CWE

CWE-353

Missing Support for Integrity Check

{"id": "CVE-2026-33261", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-33261", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-04-22T17:52:56.932119Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security@open-xchange.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.9, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.2}]}, "affected": [{"source": "security@open-xchange.com", "affectedData": [{"repo": "https://github.com/PowerDNS/pdns", "vendor": "PowerDNS", "modules": ["Aggressive use of NSEC cache"], "product": "Recursor", "versions": [{"status": "affected", "version": "5.4.0", "lessThan": "5.4.1", "versionType": "semver"}, {"status": "affected", "version": "5.3.0", "lessThan": "5.3.6", "versionType": "semver"}, {"status": "affected", "version": "5.2.0", "lessThan": "5.2.9", "versionType": "semver"}], "packageName": "pdns-recursor", "programFiles": ["aggressive_nsec.cc"], "collectionURL": "https://repo.powerdns.com/", "defaultStatus": "unaffected"}]}], "published": "2026-04-22T10:16:51.857", "references": [{"url": "https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-03.html", "tags": ["Broken Link", "Vendor Advisory"], "source": "security@open-xchange.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-353"}]}], "descriptions": [{"lang": "en", "value": "A zone transition from NSEC to NSEC3 might trigger an internal inconsistency and cause a denial of service."}], "lastModified": "2026-06-17T10:37:12.900", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EBDA7C62-FAD4-470C-A6FE-4CF19B0BD4AD", "versionEndExcluding": "5.2.9", "versionStartIncluding": "5.2.0"}, {"criteria": "cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9F7AC884-348F-47B1-8853-49BFEDBEA9EA", "versionEndExcluding": "5.3.6", "versionStartIncluding": "5.3.0"}, {"criteria": "cpe:2.3:a:powerdns:recursor:5.4.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4B201BAD-5A74-45E9-91FD-5E950BA18BF3"}], "operator": "OR"}]}], "sourceIdentifier": "security@open-xchange.com"}