Published Oct 21, 2026Sources checked Oct 30, 2026
7.5HIGHCVSS out of 10
What this means
Review the available evidence
CVE-2026-19630 and is rated High severity with a CVSS score of 7.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Oct 30, 2026
Release Notes
CISA KEVNot listedBased on the latest collected catalog
EPSS0.4%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-19630?
In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with no limit imposed by BIND. A DNS message with a maliciously large number of such structures will cause BIND to consume disproportionate amounts of CPU time and memory during processing.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.29, 9.21.0 through 9.21.26, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.29-S1.