An issue was discovered in net/ipv6/ip6mr.c in the Linux kernel...

Vulnerability Description

An issue was discovered in net/ipv6/ip6mr.c in the Linux kernel before 4.11. By setting a specific socket option, an attacker can control a pointer in kernel land and cause an inet_csk_listen_stop general protection fault, or potentially execute arbitrary code under certain circumstances. The issue can be triggered as root (e.g., inside a default LXC container or with the CAP_NET_ADMIN capability) or after namespace unsharing. This occurs because sk_type and protocol are not checked in the appropriate part of the ip6_mroute_* functions. NOTE: this affects Linux distributions that use 4.9.x longterm kernels before 4.9.187.

References

• https://pulsesecurity.co.nz/advisories/linux-kernel-4.9-inetcsklistenstop-gpf
• https://salsa.debian.org/kernel-team/linux/commit/baefcdc2f29923e7325ce4e1a72c3ff0a9800f32
• https://lists.openwall.net/netdev/2017/12/04/40
• https://github.com/torvalds/linux/commit/99253eb750fda6a644d5188fb26c43bad8d5a745
• https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=99253eb750fda6a644d5188fb26c43bad8d5a745
• https://www.debian.org/security/2019/dsa-4497
• https://lists.debian.org/debian-lts-announce/2019/08/msg00016.html
• https://seclists.org/bugtraq/2019/Aug/26
• https://lists.debian.org/debian-lts-announce/2019/08/msg00017.html
• http://packetstormsecurity.com/files/154059/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html
• https://support.f5.com/csp/article/K41582535
• https://usn.ubuntu.com/4145-1/
• https://support.f5.com/csp/article/K41582535?utm_source=f5support&amp%3Butm_medium=RSS