ELA-230-1 bind9 security update

Fix for denial of service due to bad checks

Related CVE CVE-2020-8616 CVE-2020-8617

Several vulnerabilities were discovered in BIND, a DNS server implementation.


It was discovered that BIND does not sufficiently limit the number
of fetches performed when processing referrals. An attacker can take
advantage of this flaw to cause a denial of service (performance
degradation) or use the recursing server in a reflection attack with
a high amplification factor.


It was discovered that a logic error in the code which checks TSIG
validity can be used to trigger an assertion failure, resulting in
denial of service.

For Debian 7 Wheezy, these problems have been fixed in version 1:9.8.4.dfsg.P1-6+nmu2+deb7u24.

We recommend that you upgrade your bind9 packages.

Further information about Extended LTS security advisories can be found at: https://deb.freexian.com/extended-lts/