Debian Security Advisory

DLA-798-1 pdns -- LTS security update

Date Reported:
25 Jan 2017
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2016-2120, CVE-2016-7068, CVE-2016-7072, CVE-2016-7073, CVE-2016-7074.
More information:

Multiple vulnerabilities have been discovered in pdns, an authoritative DNS server. The Common Vulnerabilities and Exposures project identifies the following problems:

  • CVE-2016-2120

    Mathieu Lafon discovered that pdns does not properly validate records in zones. An authorized user can take advantage of this flaw to crash server by inserting a specially crafted record in a zone under their control and then sending a DNS query for that record.

  • CVE-2016-7068

    Florian Heinz and Martin Kluge reported that pdns parses all records present in a query regardless of whether they are needed or even legitimate, allowing a remote, unauthenticated attacker to cause an abnormal CPU usage load on the pdns server, resulting in a partial denial of service if the system becomes overloaded.

  • CVE-2016-7072

    Mongo discovered that the webserver in pdns is susceptible to a denial-of-service vulnerability. A remote, unauthenticated attacker to cause a denial of service by opening a large number of f TCP connections to the web server.

  • CVE-2016-7073 / CVE-2016-7074

    Mongo discovered that pdns does not sufficiently validate TSIG signatures, allowing an attacker in position of man-in-the-middle to alter the content of an AXFR.

For Debian 7 Wheezy, these problems have been fixed in version 3.1-4.1+deb7u3.

We recommend that you upgrade your pdns packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: