Vulnerability · Published Apr 22, 2026 · Assigned by OX
CVE-2026-33256Unbounded memory allocation by internal web server
Medium 5.3
In plain English
A medium-severity resource allocation without limits in Recursor from PowerDNS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.6%top 50.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | pdns-recursor | 5.3.6-r0 | ALPINE-CVE-2026-33256 |
| Alpine:v3.24 | pdns-recursor | 5.4.1-r0 | ALPINE-CVE-2026-33256 |
| Debian:12 | pdns-recursor | no fix listed | DEBIAN-CVE-2026-33256 |
| Debian:13 | pdns-recursor | 5.2.9-0+deb13u1 | DEBIAN-CVE-2026-33256 |
| Debian:14 | pdns-recursor | 5.4.1-1 | DEBIAN-CVE-2026-33256 |
| Ubuntu:24.04:LTS | pdns-recursor | no fix listed | UBUNTU-CVE-2026-33256 |
| Ubuntu:25.10 | pdns-recursor | no fix listed | UBUNTU-CVE-2026-33256 |
| Ubuntu:26.04:LTS | pdns-recursor | no fix listed | UBUNTU-CVE-2026-33256 |
| Ubuntu:26.10 | pdns-recursor | no fix listed | UBUNTU-CVE-2026-33256 |
Affected products (as reported)
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L