High severity · published Apr 22, 2026
CVE-2026-33256
Unbounded memory allocation by internal web server
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
An attacker can send a web request that causes unlimited memory allocation in the internal web server, leading to a denial of service. The internal web server is disabled by default.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% 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-2026-33256
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33256
Broken Link
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-powerdns-2026-03.html
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