1. Ubuntu Security Notices
  2. USN-4698-1

USN-4698-1: Dnsmasq vulnerabilities

Publication date

19 January 2021

Overview

Several security issues were fixed in Dnsmasq.

Releases

Packages

  • dnsmasq - Small caching DNS proxy and DHCP/TFTP server

Details

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
memory when sorting RRsets. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25681, CVE-2020-25687)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
extracting certain names. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25682, CVE-2020-25683)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly
implemented address/port checks. A remote attacker could use this issue to
perform a cache poisoning attack. (CVE-2020-25684)

Moshe Kol and...

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
memory when sorting RRsets. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25681, CVE-2020-25687)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
extracting certain names. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25682, CVE-2020-25683)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly
implemented address/port checks. A remote attacker could use this issue to
perform a cache poisoning attack. (CVE-2020-25684)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly
implemented query resource name checks. A remote attacker could use this
issue to perform a cache poisoning attack. (CVE-2020-25685)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
multiple query requests for the same resource name. A remote attacker could
use this issue to perform a cache poisoning attack. (CVE-2020-25686)

It was discovered that Dnsmasq incorrectly handled memory during DHCP
response creation. A remote attacker could possibly use this issue to
cause Dnsmasq to consume resources, leading to a denial of service. This
issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04
LTS. (CVE-2019-14834)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
20.10 groovy dnsmasq –  2.82-1ubuntu1.1
dnsmasq-base –  2.82-1ubuntu1.1
dnsmasq-utils –  2.82-1ubuntu1.1
20.04 focal dnsmasq –  2.80-1.1ubuntu1.2
dnsmasq-base –  2.80-1.1ubuntu1.2
dnsmasq-utils –  2.80-1.1ubuntu1.2
18.04 bionic dnsmasq –  2.79-1ubuntu0.2
dnsmasq-base –  2.79-1ubuntu0.2
dnsmasq-utils –  2.79-1ubuntu0.2
16.04 xenial dnsmasq –  2.75-1ubuntu0.16.04.7
dnsmasq-base –  2.75-1ubuntu0.16.04.7
dnsmasq-utils –  2.75-1ubuntu0.16.04.7

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References

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