Ntp · Ntp · CVE-2018-7182
**Name of the Vulnerable Software and Affected Versions**
ntp versions 4.2.8p6 through 4.2.8p10
**Description**
The issue is related to the `ctl getitem` method in `ntpd`, which is part of the NTP protocol implementation. It involves a buffer read beyond its boundaries in memory. This can be exploited by a remote attacker using specially crafted mode 6 packets, potentially leading to a denial of service. Additionally, there's a concern about the failure to prevent Sybil attacks from authenticated peers, which could allow an attacker to bypass security restrictions and modify a victim's clock by creating multiple ephemeral associations.
**Recommendations**
For versions 4.2.8p6 through 4.2.8p10, update to version 4.2.8p11 or later to resolve the issue.
As a temporary workaround, consider restricting access to mode 6 packets to minimize the risk of exploitation.
Restrict the ability to create multiple ephemeral associations to prevent Sybil attacks.