1. Ubuntu Security Notices
  2. USN-4969-1

USN-4969-1: DHCP vulnerability

Publication date

27 May 2021

Overview

DHCP could be made to crash if it received specially crafted network traffic.

Releases

Packages

Details

Jon Franklin and Pawel Wieczorkiewicz discovered that DHCP incorrectly
handled lease file parsing. A remote attacker could possibly use this issue
to cause DHCP to crash, resulting in a denial of service.

Jon Franklin and Pawel Wieczorkiewicz discovered that DHCP incorrectly
handled lease file parsing. A remote attacker could possibly use this issue
to cause DHCP to crash, resulting in a denial of service.

Update instructions

In general, a standard system update will 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
21.04 hirsute isc-dhcp-client –  4.4.1-2.2ubuntu6.1
isc-dhcp-server –  4.4.1-2.2ubuntu6.1
20.10 groovy isc-dhcp-client –  4.4.1-2.1ubuntu10.1
isc-dhcp-server –  4.4.1-2.1ubuntu10.1
20.04 focal isc-dhcp-client –  4.4.1-2.1ubuntu5.20.04.2
isc-dhcp-server –  4.4.1-2.1ubuntu5.20.04.2
18.04 bionic isc-dhcp-client –  4.3.5-3ubuntu7.3
isc-dhcp-server –  4.3.5-3ubuntu7.3

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References

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