Debian Security Advisory

DSA-4689-1 bind9 -- security update

Date Reported:
19 May 2020
Affected Packages:
Security database references:
In the Debian bugtracking system: Bug 945171.
In Mitre's CVE dictionary: CVE-2019-6477, CVE-2020-8616, CVE-2020-8617.
More information:

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

  • CVE-2019-6477

    It was discovered that TCP-pipelined queries can bypass tcp-client limits resulting in denial of service.

  • CVE-2020-8616

    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.

  • CVE-2020-8617

    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 the oldstable distribution (stretch), these problems have been fixed in version 1:9.10.3.dfsg.P4-12.3+deb9u6.

For the stable distribution (buster), these problems have been fixed in version 1:9.11.5.P4+dfsg-5.1+deb10u1.

We recommend that you upgrade your bind9 packages.

For the detailed security status of bind9 please refer to its security tracker page at: