The check_alu_op function in kernel/bpf/verifier.c in the Linux kernel through 4.4 allows local users to cause a denial of service (memory corruption) or possibly have unspecified other impact by leveraging incorrect sign extension.
http://openwall.com/lists/oss-security/2017/12/21/2
http://www.securityfocus.com/bid/102288
https://bugs.chromium.org/p/project-zero/issues/detail?id=1454
https://github.com/torvalds/linux/commit/95a762e2c8c942780948091f8f2a4f32fce1ac6f
https://usn.ubuntu.com/3619-1/
https://usn.ubuntu.com/3619-2/
https://usn.ubuntu.com/3633-1/
https://usn.ubuntu.com/usn/usn-3523-2/
https://www.debian.org/security/2017/dsa-4073
https://www.exploit-db.com/exploits/44298/
Source: MITRE
Published: 2017-12-27
Updated: 2021-01-05
Type: CWE-119
Base Score: 7.2
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 3.9
Severity: HIGH
Base Score: 7.8
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 1.8
Severity: HIGH