#VU11528 Infinite loop in FreeBSD - CVE-2018-6918

Vulnerability identifier: #VU11528

Vulnerability risk: Medium

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:Green]

CVE-ID: CVE-2018-6918

CWE-ID: CWE-835

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
FreeBSD
Operating systems & Components / Operating system

Vendor: FreeBSD Foundation

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

The weakness exists due to the length field of the option header does not count the size of the option header itself and pointer/offset mistakes in the handling of IPv4 options. A remote attacker can trigger infinite loop and cause the service to crash.

Mitigation
Install update from vendor's website.

Vulnerable software versions

FreeBSD: 11.0 - 11.1

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External links
https://www.freebsd.org/security/advisories/FreeBSD-SA-18:05.ipsec.asc

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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.