DNS cache poisoning via insufficient delegation validation
Published Feb 9, 2026 · Updated Feb 9, 2026
DNS cache poisoning in PowerDNS Recursor 5.1.0 through 5.1.7, 5.2.0 through 5.2.5, and 5.3.0 allows remote attackers to corrupt delegations. The synchronous resolver accepts spoofed delegation information from authoritative-server responses without strict enough validation and stores it in the delegation cache. Successful exploitation requires spoofed crafted DNS packets; cached attacker-influenced delegations can affect later resolution, but the vendor reports no system compromise.
Summary
What happened
DNS cache poisoning in PowerDNS Recursor 5.1.0 through 5.1.7, 5.2.0 through 5.2.5, and 5.3.0 allows remote attackers to corrupt delegations. The synchronous resolver accepts spoofed delegation information from authoritative-server responses without strict enough validation and stores it in the delegation cache. Successful exploitation requires spoofed crafted DNS packets; cached attacker-influenced delegations can affect later resolution, but the vendor reports no system compromise.
The record
- CVE
- CVE-2025-59023
- Published
- Feb 9, 2026
- Updated
- Feb 9, 2026
- Vendor
- PowerDNS
- Product
- PowerDNS Recursor
- Classifications
- CWE-294, T1565.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 9, 2026CVE publishedPublication date reported by the CVE source.
- Feb 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.1.0 <5.1.8
- Affected versionversion=5.2.0 <5.2.6
- Affected versionversion=5.3.0 <5.3.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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