#VU67944 Input validation error in DHCP - CVE-2022-2928

Vulnerability identifier: #VU67944

Vulnerability risk: Low

CVSSv4.0: 2.3 [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]

CVE-ID: CVE-2022-2928

CWE-ID: CWE-20

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
DHCP
Server applications / Other server solutions

Vendor: ISC

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

DHCP: 2.0, 3.0 - 3.0.7, 3.1-ESV-R1 - 3.1.3, 4.0-esv - 4.0.3, 4.1-ESV-R1 - 4.1.2, 4.2.0-P1 - 4.2.8, 4.3.0 rc1 - 4.3.6, 4.4.0 b1 - 4.4.3

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External links
https://kb.isc.org/docs/cve-2022-2928

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.