Vulnerability Report

CVE-2021-3492

Title: Shiftfs Double-Free or Memory Leak Privilege Escalation

DoS/Privilege Escalation

Proof Of Concept

PoC Available for CVE-2021-3492

CWE Category CWE-401
Published Date Apr 17, 2021
Modified Date Nov 21, 2024
Exploit Status Available
Score 8.8 CVSS v3.1
Exploit Probability (EPSS)
1.55%

Vulnerability Summary

CVE-2021-3492: 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.

Impacted Vendors

U
ubuntu 1
C
canonical 1

Reference Links

http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333 https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6 https://ubuntu.com/security/notices/USN-4917-1 https://www.openwall.com/lists/oss-security/2021/04/16/2 https://www.zerodayinitiative.com/advisories/ZDI-21-422/ http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333 https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6 https://ubuntu.com/security/notices/USN-4917-1 https://www.openwall.com/lists/oss-security/2021/04/16/2 https://www.zerodayinitiative.com/advisories/ZDI-21-422/
CVSS v3.1
Source Entity [email protected]
Severity HIGH
8.8
Attack Vector
LOCAL
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
CHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v3.1
Source Entity [email protected]
Severity HIGH
7.8
Attack Vector
LOCAL
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v2.0
Source Entity [email protected]
Severity HIGH
7.2
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:L/AC:L/Au:N/C:C/I:C/A:C

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2021-3492 Exploits & PoCs (Proof Of Concept)

GitHub https://github.com/synacktiv/CVE-2021-3492
View Code
MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector LOCAL
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected Stack

No specific products linked.