#VU12304 Incorrect calcualtion in ntp - CVE-2016-7433

Vulnerability identifier: #VU12304

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-2016-7433

CWE-ID: CWE-682

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ntp
Server applications / Other server solutions

Vendor: ntp.org

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

The weakness exists due to improper performance of the initial sync calculations. A remote attacker can cause the service to crash via unknown vectors, related to a "root distance that did not include the peer dispersion."

Mitigation
Update to version 4.2.8p9.

Vulnerable software versions

ntp: 4.2.8p1 - 4.2.8p8

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External links
https://www.nwtime.org/ntp428p9_release/

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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.