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.
Exploits (1)
References (6)
Core 6
Core References
Mailing List, Third Party Advisory x_refsource_misc
https://www.openwall.com/lists/oss-security/2021/04/16/2
Mailing List, Patch, Vendor Advisory x_refsource_misc
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6
Mailing List, Patch, Vendor Advisory x_refsource_misc
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333
Vendor Advisory x_refsource_misc
https://ubuntu.com/security/notices/USN-4917-1
Third Party Advisory, VDB Entry x_refsource_misc
https://www.zerodayinitiative.com/advisories/ZDI-21-422/
Third Party Advisory, VDB Entry x_refsource_misc
http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html
Scores
CVSS v3
8.8
EPSS
0.2444
EPSS Percentile
96.1%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Details
CWE
CWE-415
CWE-401
Status
published
Products (2)
canonical/ubuntu_linux
< 18.04
canonical/ubuntu_linux
< 20.10
Published
Apr 17, 2021
Tracked Since
Feb 18, 2026