Ntp

ntpd in NTP 4.2.8p3 and NTPsec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 relies on the underlying operating system to protect it from requests that impersonate reference clocks. Because reference clocks are treated like other peers and stored in the same structure, any packet with a source ip address of a reference clock (127.127.1.1 for example) that reaches the receive() function will match that reference clock's peer record and will be treated as a trusted peer. Any system that lacks the typical martian packet filtering which would block these packets is in danger of having its time controlled by an attacker.Show less

NTP before 4.2.8p9 changes the peer structure to the interface it receives the response from a source, which allows remote attackers to cause a denial of service (prevent communication with a source) by sending a response for a source to an interface the source does not use.Show less

NTP before 4.2.8p9 rate limits responses received from the configured sources when rate limiting for all associations is enabled, which allows remote attackers to cause a denial of service (prevent responses from the sources) by sending responses with a spoofed source address.Show less

An exploitable vulnerability exists in the message authentication functionality of libntp in ntp 4.2.8p4 and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92. An attacker can send a series of crafted messages to attempt to recover the message digest key.Show less

A malicious authenticated peer can create arbitrarily-many ephemeral associations in order to win the clock selection algorithm in ntpd in NTP 4.2.8p4 and earlier and NTPsec 3e160db8dc248a0bcb053b56a80167dc742d2b74 and a5fb34b9cc89b92a8fef2f459004865c93bb7f92 and modify a victim's clock.Show less

An attacker can spoof a packet from a legitimate ntpd server with an origin timestamp that matches the peer->dst timestamp recorded for that server. After making this switch, the client in NTP 4.2.8p4 and earlier and NTPSec aa48d001683e5b791a743ec9c575aaf7d867a2b0c will reject all future legitimate server responses. It is possible to force the victim client to move time after the mode has been changed. ntpq gives no indication that the mode has been switched.Show less

An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This is true even if authentication is enabled.Show less

An integer overflow can occur in NTP-dev.4.3.70 leading to an out-of-bounds memory copy operation when processing a specially crafted private mode packet. The crafted packet needs to have the correct message authentication code and a valid timestamp. When processed by the NTP daemon, it leads to an immediate crash.Show less