CVE-2021-3492 Detail

Current Description

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.


View Analysis Description

Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  7.8 HIGH
Vector:  CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Nist CVSS score does not match with CNA score
CNA:  Canonical Ltd.
Base Score:  8.8 HIGH
Vector:  CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: It is possible that the NVD CVSS may not match that of the CNA. The most common reason for this is that publicly available information does not provide sufficient detail or that information simply was not available at the time the CVSS vector string was assigned.

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
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333 Mailing List  Patch  Vendor Advisory 
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6 Mailing List  Patch  Vendor Advisory 
https://ubuntu.com/security/notices/USN-4917-1 Vendor Advisory 
https://www.openwall.com/lists/oss-security/2021/04/16/2 Mailing List  Third Party Advisory 
https://www.zerodayinitiative.com/advisories/ZDI-21-422/ Third Party Advisory  VDB Entry 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-415 Double Free cwe source acceptance level NIST   Contributor acceptance level Canonical Ltd.  
CWE-401 Missing Release of Memory after Effective Lifetime cwe source acceptance level NIST   Contributor acceptance level Canonical Ltd.  

Known Affected Software Configurations Switch to CPE 2.2

CPEs loading, please wait.

Denotes Vulnerable Software
Are we missing a CPE here? Please let us know.

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-3492
NVD Published Date:
04/17/2021
NVD Last Modified:
04/22/2021
Source:
Canonical Ltd.