A DNSSEC validating resolver that is under a random...
High severity
Unreviewed
Published
Jul 22, 2026
to the GitHub Advisory Database
•
Updated Jul 22, 2026
Description
Published by the National Vulnerability Database
Jul 22, 2026
Published to the GitHub Advisory Database
Jul 22, 2026
Last updated
Jul 22, 2026
A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the
max-cache-sizeparameter.This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
References