CVE-2026-19401

Description

A flaw was found in NSD. A remote attacker can crash an NSD server child by sending a specially crafted message containing a specific number of DNS Cookie options. This continuous crashing can severely hamper or deny DNS service, leading to a denial of service (DoS) condition. This vulnerability primarily affects debugging or non-release build types of NSD.

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

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

An attacker that can trigger an assert statement can still lead to a denial of service if the relevant code can be triggered by an attacker, and if the scope of the assert() extends beyond the attacker's own session.

Frequently Asked Questions

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