NTP BUG 2667: Buffer overflow in crypto_recv()
Last update: April 22, 2024 18:49 UTC (7e7bd5857)
Summary
Description
When Autokey Authentication is enabled (i.e. the ntp.conf file contains a crypto pw ... directive) a remote attacker can send a carefully crafted packet that can overflow a stack buffer and potentially allow malicious code to be executed with the privilege level of the ntpd process.
Mitigation
Any of:
- Upgrade to 4.2.8 or later.
- Disable Autokey Authentication by removing, or commenting out, all configuration directives beginning with the
crypto keyword in your ntp.conf file.
- Put
restrict ... noquery in your ntp.conf file, for non-trusted senders.
Credit
This vulnerability was discovered by Stephen Roettger of the Google Security Team.
Timeline