#VU10791 Memory corruption in DHCP - CVE-2018-5733

Vulnerability identifier: #VU10791

Vulnerability risk: Low

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-5733

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
DHCP
Server applications / Other server solutions

Vendor: ISC

Description
The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists in the dhcpd due to improper handling of reference counting when processing client requests. A remote attacker can send large amounts of data to the target server can send a large number of packets, trigger a reference counter overflow and cause the target dhcpd service to consume all available memory and crash.

Mitigation
Update to versions 4.1-ESV-R15-P1, 4.3.6-P1 or 4.4.1.

Vulnerable software versions

DHCP: 4.1.0, 4.2.0, 4.3.0, 4.4.0

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External links
https://kb.isc.org/article/AA-01567/0/CVE-2018-5733%3A-A-malicious-client-can-overflow-a-reference-c...

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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 Internet.

Is there known malware, which exploits this vulnerability?

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