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-2026-33601 (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 zoneToCache() function when interacting with a malicious authoritative server. An attacker can cause a null pointer dereference by sending a specially crafted zone, resulting in a denial of service.