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Ubuntu Security Notice USN-5626-1
September 21, 2022

bind9 vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in Bind.

Software Description:
- bind9: Internet Domain Name Server

Details:

Yehuda Afek, Anat Bremler-Barr, and Shani Stajnrod discovered that Bind
incorrectly handled large delegations. A remote attacker could possibly use
this issue to reduce performance, leading to a denial of service.
(CVE-2022-2795)

It was discovered that Bind incorrectly handled statistics requests. A
remote attacker could possibly use this issue to obtain sensitive memory
contents, or cause a denial of service. This issue only affected Ubuntu
22.04 LTS. (CVE-2022-2881)

It was discovered that Bind incorrectly handled memory when processing
certain Diffie-Hellman key exchanges. A remote attacker could use this
issue to consume resources, leading to a denial of service. This issue only
affected Ubuntu 22.04 LTS. (CVE-2022-2906)

Maksym Odinintsev discovered that Bind incorrectly handled answers from
cache when configured with a zero stale-answer-timeout. A remote attacker
could possibly use this issue to cause Bind to crash, resulting in a denial
of service. This issue only affected Ubuntu 22.04 LTS. (CVE-2022-3080)

It was discovered that Bind incorrectly handled memory when processing
ECDSA DNSSEC verification. A remote attacker could use this issue to
consume resources, leading to a denial of service. This issue only affected
Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2022-38177)

It was discovered that Bind incorrectly handled memory when processing
EDDSA DNSSEC verification. A remote attacker could use this issue to
consume resources, leading to a denial of service. (CVE-2022-38178)

Update instructions:

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

Ubuntu 22.04 LTS:
  bind9                           1:9.18.1-1ubuntu1.2

Ubuntu 20.04 LTS:
  bind9                           1:9.16.1-0ubuntu2.11

Ubuntu 18.04 LTS:
  bind9                           1:9.11.3+dfsg-1ubuntu1.18

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5626-1
  CVE-2022-2795, CVE-2022-2881, CVE-2022-2906, CVE-2022-3080,
  CVE-2022-38177, CVE-2022-38178

Package Information:
  https://launchpad.net/ubuntu/+source/bind9/1:9.18.1-1ubuntu1.2
  https://launchpad.net/ubuntu/+source/bind9/1:9.16.1-0ubuntu2.11
  https://launchpad.net/ubuntu/+source/bind9/1:9.11.3+dfsg-1ubuntu1.18