Description
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-size` parameter. 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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
ISC BIND 9
Default version status: unaffected
9.11.0 to ≤ 9.18.50affected9.20.0 to ≤ 9.20.24affected9.21.0 to ≤ 9.21.23affected9.11.3-S1 to ≤ 9.18.50-S1affected9.20.9-S1 to ≤ 9.20.24-S1affected