CVE-2026-19668
Description
A flaw was found in BIND, a widely used Domain Name System (DNS) software. A remote attacker could exploit this vulnerability by sending a large number of specially crafted, invalid DNSSEC (Domain Name System Security Extensions) records to a BIND recursive resolver. This could lead to excessive resource consumption, resulting in a Denial of Service (DoS) for the affected resolver.
Statement
This Moderate impact flaw in BIND recursive resolvers can lead to a denial of service due to excessive resource consumption when processing specific invalid DNSSEC records. Red Hat's default BIND configurations include max-records-per-type and max-types-per-name limits, which help reduce the exposure and prevent a more severe impact.
Mitigation
To mitigate potential denial of service, ensure that the BIND recursive resolver's configuration includes appropriate limits for `max-records-per-type` and `max-types-per-name` within the `named.conf` file. These settings help control resource consumption when encountering invalid DNSSEC records. A restart of the `named` service is required for any configuration changes to take effect.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.3 | N/A | 5.3 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | Low | N/A | Low |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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