CVE-2018-1000200

MEDIUM

Description

The Linux Kernel versions 4.14, 4.15, and 4.16 has a null pointer dereference which can result in an out of memory (OOM) killing of large mlocked processes. The issue arises from an oom killed process's final thread calling exit_mmap(), which calls munlock_vma_pages_all() for mlocked vmas.This can happen synchronously with the oom reaper's unmap_page_range() since the vma's VM_LOCKED bit is cleared before munlocking (to determine if any other vmas share the memory and are mlocked).

References

http://seclists.org/oss-sec/2018/q2/67

http://www.securityfocus.com/bid/104397

https://access.redhat.com/errata/RHSA-2018:2948

https://access.redhat.com/security/cve/cve-2018-1000200

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=27ae357fa82be5ab73b2ef8d39dcb8ca2563483a

https://marc.info/?l=linux-kernel&m=152400522806945

https://marc.info/?l=linux-kernel&m=152460926619256

https://usn.ubuntu.com/3752-1/

https://usn.ubuntu.com/3752-2/

https://usn.ubuntu.com/3752-3/

Details

Source: MITRE

Published: 2018-06-05

Updated: 2018-10-31

Type: CWE-476

Risk Information

CVSS v2.0

Base Score: 4.9

Vector: AV:L/AC:L/Au:N/C:N/I:N/A:C

Impact Score: 6.9

Exploitability Score: 3.9

Severity: MEDIUM

CVSS v3.0

Base Score: 5.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 1.8

Severity: MEDIUM