CVE-2023-33192
Improper handling of NTS cookie length that could crash the ntpd-rs server
Description
### Impact ntpd-rs does not validate the length of NTS cookies in received NTP packets to the server. An attacker can crash the server by sending a specially crafted NTP packet containing a cookie shorter than what the server expects. The server also crashes when it is not configured to handle NTS packets. ntpd-rs running purely as an ntp client is not affected. ### Patches The issue was caused by improper slice indexing. The indexing operations were replaced by safer alternatives that do not crash the ntpd-rs server process but instead properly handle the error condition. A patch was released in version 0.3.3 ### Workarounds ntpd-rs running purely as an ntp client is not affected. By default, ntpd-rs packages are not configured to run as a server. For machines where serving the time is required, there is no known workaround. Users are recommended to upgrade ntpd-rs as soon as possible. ### References https://github.com/pendulum-project/ntpd-rs/pull/752 We would like to thank @mlichvar for identifying this issue
How to fix CVE-2023-33192
To remediate CVE-2023-33192, upgrade the affected package to a fixed version below.
- —upgrade to 0.3.3 or later
Is CVE-2023-33192 being exploited?
Low — EPSS is 0.5%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- >= 0.3.0, < 0.3.3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |