Weilong Chen <chenweil...@huawei.com> wrote: > On 2019/5/13 15:49, Michal Kubecek wrote: > > On Mon, May 13, 2019 at 09:33:13AM +0800, Weilong Chen wrote: > > > The remote host answers to an ICMP timestamp request. > > > This allows an attacker to know the time and date on your host. > > > > Why is that a problem? If it is, does it also mean that it is a security > > problem to have your time in sync (because then the attacker doesn't > > even need ICMP timestamps to know the time and date on your host)? > > > It's a low risk vulnerability(CVE-1999-0524). TCP has > net.ipv4.tcp_timestamps = 0 to disable it.
These are not the same. TCP timestamps (before pseudo-randomized offset were added) used to leaked system uptime. ICMP timestamps "leak" milliseconds since midnight. Don't see how thats a problem.
