Vulnerability identifier: #VU4013
Vulnerability risk: High
CVSSv3.1: 8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:F/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-20
Exploitation vector: Network
Exploit availability: Yes
Vulnerable software:
ntp
Server applications /
Other server solutions
Vendor: ntp.org
Description
The vulnerability allows a remote attacker to cause DoS conditions on the target system.
The weakness exists due to an error in the monlist feature in ntp_request.c. By sending a specially crafted REQ_MON_GETLIST or REQ_MON_GETLIST_1 request, a remote attacker can consume available CPU resources and cause the server to crash.
Successful exploitation of the vulnerability results in denial of service on the vulnerable system.
Note: the vulnerability was being actively exploited.
Mitigation
Update to version 4.2.7p26.
Vulnerable software versions
ntp: 4.2.7 - 4.2.7p25
External links
http://aix.software.ibm.com/aix/efixes/security/ntp_advisory.asc
http://bugs.ntp.org/show_bug.cgi?id=1532
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. However, a fully functional exploit for this vulnerability is available.