In BIND before version 9.16.22, exploitation of broken authoritative servers using a flaw in response processing can cause degradation in BIND resolver performance. The way the lame cache is currently designed makes it possible for its internal data structures to grow almost infinitely, which may cause significant delays in client query processing.
In BIND before version 9.16.22, exploitation of broken authoritative servers using a flaw in response processing can cause degradation in BIND resolver performance. The way the lame cache is currently designed makes it possible for its internal data structures to grow almost infinitely, which may cause significant delays in client query processing.
https://kb.isc.org/v1/docs/cve-2021-25219 https://github.com/isc-projects/bind9/commit/8fe18c0566c41228a568157287f5a44f96d37662
Workaround ========== Setting lame-ttl 0; disables the lame cache and prevents the performance issue.
Vulmon