ELA-418-1 bind9 security update

several vulnerabilities

Related CVEs CVE-2021-25214 CVE-2021-25215 CVE-2021-25216

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


Greg Kuechle discovered that a malformed incoming IXFR transfer
could trigger an assertion failure in named, resulting in denial
of service.


Siva Kakarla discovered that named could crash when a DNAME record
placed in the ANSWER section during DNAME chasing turned out to be
the final answer to a client query.


It was discovered that the SPNEGO implementation used by BIND is
prone to a buffer overflow vulnerability. This update switches to
use the SPNEGO implementation from the Kerberos libraries.

For Debian 8 jessie, these problems have been fixed in version 1:9.9.5.dfsg-9+deb8u22.

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/