Inefficient Algorithmic Complexity Affecting unbound package, versions [,1.25.1)
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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Test your applications- Snyk IDSNYK-UNMANAGED-UNBOUND-17111519
- published31 May 2026
- disclosed20 May 2026
- creditQifan Zhang
Introduced: 20 May 2026
CVE-2026-42923 (opens in a new tab)How to fix?
Upgrade unbound to version 1.25.1 or higher.
Overview
Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the negative cache code path when processing NSEC3 records with high iteration counts. An attacker can degrade DNS resolution performance for other resolver threads by causing excessive hash computations while a global lock is held.