Medium severity · published Apr 22, 2026
CVE-2026-33261
Null pointer accces in aggressive NSEC(3) cache
5.9
CVSS
0.2%
EPSS
No
On KEV
Description
A zone transition from NSEC to NSEC3 might trigger an internal inconsistency and cause a denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
Recursor · PowerDNS
5.4.0 before 5.4.1; 5.3.0 before 5.3.6; 5.2.0 before 5.2.9 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33261
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33261
Broken Link
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-03.html
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