NULL Pointer Dereference Affecting pdns-recursor package, versions [,5.2.9)[5.3.0-alpha1,5.3.6)[5.4.0-alpha1,5.4.1)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published24 Apr 2026
- disclosed23 Apr 2026
- creditUnknown
Introduced: 23 Apr 2026
CVE-2026-33261 (opens in a new tab)How to fix?
Upgrade pdns-recursor to version 5.2.9, 5.3.6, 5.4.1 or higher.
Overview
Affected versions of this package are vulnerable to NULL Pointer Dereference in the NSEC(3) cache. An attacker can cause a denial of service by triggering a zone transition from NSEC to NSEC3, which leads to an internal inconsistency and a null pointer access.