Artem S. Tashkinov writes: The Register reports that it is possible to crash network-facing Linux servers, PCs, smartphones and tablets, and gadgets, or slow down their network connections, by sending them a series of maliciously crafted packets. It is also possible to hamper FreeBSD machines with the same attack. Patches and mitigations are available, and can be applied by hand if needed, or you can wait for a security fix to be pushed or offered to your at-risk device. A key workaround is to set /proc/sys/net/ipv4/tcp_sack to 0. At the heart of the drama is a programming flaw dubbed SACK Panic aka CVE-2019-11477: this bug can be exploited to remotely crash systems powered by Linux kernel version 2.6.29 or higher, which was released 10 years ago.