CVE-2018-12633

Severity CVSS v4.0:

Pending analysis

Type:

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Publication date:

22/06/2018

Last modified:

21/08/2018

Description

An issue was discovered in the Linux kernel through 4.17.2. vbg_misc_device_ioctl() in drivers/virt/vboxguest/vboxguest_linux.c reads the same user data twice with copy_from_user. The header part of the user data is double-fetched, and a malicious user thread can tamper with the critical variables (hdr.size_in and hdr.size_out) in the header between the two fetches because of a race condition, leading to severe kernel errors, such as buffer over-accesses. This bug can cause a local denial of service and information leakage.

Impact

Vector 3.x

CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 6.30 MEDIUM
Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H

Attack Vector (AV): Local
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): None
Availability (A): High

Base Score 3.x

6.30

Severity 3.x

MEDIUM

Vector 2.0

AV:L/AC:M/Au:N/C:C/I:N/A:C CVSS v2.0 Severity and Metrics:

Base Score: 6.30 MEDIUM
Vector: AV:L/AC:M/Au:N/C:C/I:N/A:C

Attack Vector (AV): Local
Attack Complexity (AC): Medium
Authentication (Au): None
Confidentiality (C): Complete
Integrity (I): None
Availability (A): Complete