National Vulnerability Database

National Vulnerability Database

National Vulnerability
Database

CVE-2017-1000405 Detail

Current Description

The Linux Kernel versions 2.6.38 through 4.14 have a problematic use of pmd_mkdirty() in the touch_pmd() function inside the THP implementation. touch_pmd() can be reached by get_user_pages(). In such case, the pmd will become dirty. This scenario breaks the new can_follow_write_pmd()'s logic - pmd can become dirty without going through a COW cycle. This bug is not as severe as the original "Dirty cow" because an ext4 file (or any other regular file) cannot be mapped using THP. Nevertheless, it does allow us to overwrite read-only huge pages. For example, the zero huge page and sealed shmem files can be overwritten (since their mapping can be populated using THP). Note that after the first write page-fault to the zero page, it will be replaced with a new fresh (and zeroed) thp.

Source:  MITRE      Last Modified:  11/30/2017      View Analysis Description

Quick Info

CVE Dictionary Entry:
CVE-2017-1000405
Original release date:
11/30/2017
Last revised:
02/12/2018
Source:
US-CERT/NIST

Impact

CVSS Severity (version 3.0):
CVSS v3 Base Score:
7.0 High
Vector:
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H (legend)
Impact Score:
5.9
Exploitability Score:
1.0
CVSS Version 3 Metrics:
Attack Vector (AV):
Local
Attack Complexity (AC):
High
Privileges Required (PR):
Low
User Interaction (UI):
None
Scope (S):
Unchanged
Confidentiality (C):
High
Integrity (I):
High
Availability (A):
High
CVSS Severity (version 2.0):
CVSS v2 Base Score:
6.9 MEDIUM
Vector:
(AV:L/AC:M/Au:N/C:C/I:C/A:C) (legend)
Impact Subscore:
10.0
Exploitability Subscore:
3.4
CVSS Version 2 Metrics:
Access Vector:
Locally exploitable
Access Complexity:
Medium
Authentication:
Not required to exploit
Impact Type:
Allows unauthorized disclosure of information; Allows unauthorized modification; Allows disruption of service

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to nvd@nist.gov.

Hyperlink Resource Type Source Name
http://www.securityfocus.com/bid/102032 Third Party Advisory; VDB Entry External Source BID 102032
http://www.securitytracker.com/id/1040020 External Source SECTRACK 1040020
https://access.redhat.com/errata/RHSA-2018:0180 External Source REDHAT RHSA-2018:0180
https://medium.com/bindecy/huge-dirty-cow-cve-2017-1000405-110eca132de0 Exploit; Issue Tracking; Third Party Advisory External Source MISC https://medium.com/bindecy/huge-dirty-cow-cve-2017-1000405-110eca132de0
https://source.android.com/security/bulletin/pixel/2018-02-01 External Source CONFIRM https://source.android.com/security/bulletin/pixel/2018-02-01
https://www.exploit-db.com/exploits/43199/ Exploit; Issue Tracking; Third Party Advisory; VDB Entry External Source EXPLOIT-DB 43199

Technical Details

Vulnerability Type (View All)

Change History 6 change records found - show changes