CVE-2023-4236

A flaw was found in the Bind package. The networking code handling DNS-over-TLS queries may cause named to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load. A named instance vulnerable to this flaw may terminate unexpectedly when subjected to significant DNS-over-TLS query load.

This flaw does not affect DNS-over-HTTPS code, as that uses a different TLS implementation.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Disabling listening for DNS-over-TLS connections (by removing listen-on ... tls ... { ... }; statements from the configuration) prevents the affected code paths from being taken, rendering exploitation impossible. However, there is no workaround for this flaw if DNS-over-TLS support is required.