SB2022112119 - Ubuntu update for isc-dhcp
Published: November 21, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Input validation error (CVE-ID: CVE-2022-2928)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to an error related to the way processing lease queries are processed by the DHCP server. With a DHCP server configured with "allow leasequery;" a remote attacker can send lease queries for the same lease multiple times, leading to the "add_option()" function being repeatedly called. This can cause an option's "refcount" field to overflow and the server to abort.
2) Memory leak (CVE-ID: CVE-2022-2929)
CWE-ID: CWE-401 - Missing release of memory after effective lifetime
CVSSv4: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to perform DoS attack on the target system.
The vulnerability exists due memory leak within the fqdn_universe_decode() function when processing DHCP packets with DNS labels. A remote attacker can send specially crafted DHCP packets to the affected server, trigger memory leak and perform denial of service attack.
Remediation
Install update from vendor's website.