CVE-2026-33610
Description
A flaw was found in PowerDNS. A remote attacker, operating as a rogue primary server, can exploit this vulnerability by sending a malicious DNS update request to a PowerDNS secondary server. This can lead to the exhaustion of file descriptors on the secondary server. Consequently, the PowerDNS secondary server may experience a Denial of Service (DoS), making it unable to process legitimate requests.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Mitigation
To mitigate this issue, restrict network access to PowerDNS secondary servers, allowing DNS update requests only from trusted primary servers. Implement firewall rules to limit incoming connections on port 53 (TCP/UDP) to known, legitimate primary DNS servers. If DNS update forwarding is not a required function, consider disabling it within the PowerDNS configuration. Any changes to network configuration or PowerDNS settings may require a service reload or restart to take effect and could impact DNS resolution if not properly configured.
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (Other); DoS: Resource Consumption (Memory); DoS: Resource Consumption (CPU)
An attacker that can influence the allocation of resources that are not properly released could deplete the available resource pool and prevent all other processes from accessing the same type of resource. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.
Frequently Asked Questions
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