The HMAC implementation (crypto/hmac.c) in the Linux kernel before 4.14.8 does not validate that the underlying cryptographic hash algorithm is unkeyed, allowing a local attacker able to use the AF_ALG-based hash interface (CONFIG_CRYPTO_USER_API_HASH) and the SHA-3 hash algorithm (CONFIG_CRYPTO_SHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.8
https://www.debian.org/security/2018/dsa-4082
https://www.debian.org/security/2017/dsa-4073
https://usn.ubuntu.com/3632-1/
https://usn.ubuntu.com/3619-2/
https://usn.ubuntu.com/3619-1/
https://usn.ubuntu.com/3617-3/
https://usn.ubuntu.com/3617-2/
https://usn.ubuntu.com/3617-1/
https://usn.ubuntu.com/3583-2/
https://usn.ubuntu.com/3583-1/
https://lists.debian.org/debian-lts-announce/2018/01/msg00004.html
https://github.com/torvalds/linux/commit/af3ff8045bbf3e32f1a448542e73abb4c8ceb6f1
https://access.redhat.com/errata/RHSA-2018:2948
http://www.securityfocus.com/bid/102293
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00016.html
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00014.html
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00008.html
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00007.html
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00006.html