What’s Vulnerable › Vulnerabilities
CVE-2026-33259: Concurrent modification of RPZ data can lead to denial of servce
- Severity: medium (CVSS 5.0 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-04-22 · updated 2026-10-26
- Weakness: CWE-416
Description
Having many concurrent transfers of the same RPZ can lead to inconsistent RPZ data, use after free and/or a crash of the recursor. Normally concurrent transfers of the same RPZ zone can only occur with a malfunctioning RPZ provider.
Affected products
- PowerDNS Recursor: from 5.2.0 before 5.2.9; from 5.3.0 before 5.3.6; 5.4.0 — fixed in 5.2.9, 5.3.6
How to fix
Upgrade to a fixed version: PowerDNS Recursor 5.2.9, 5.3.6. Check the vendor advisory for mitigations.
References
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