CVE-2021-3492
8.8 HIGHShiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_...
Published: 2021-04-17 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 8.8 HIGH
- Vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- CWE
- CWE-401, CWE-415
Affected products
| Vendor | Product |
|---|---|
| canonical | ubuntu_linux |
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.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3492
- [Other]http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html
- [Patch]https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333
- [Patch]https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6
- [Vendor advisory]https://ubuntu.com/security/notices/USN-4917-1
- [Other]https://www.openwall.com/lists/oss-security/2021/04/16/2
- [Other]https://www.zerodayinitiative.com/advisories/ZDI-21-422/
- [Other]http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1.html
- [Patch]https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c891a949bf918b59cbc6e4932015ba4c35c333
- [Patch]https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee52ab9da87d82bc6de9ebb3480fff9b4d53e6
- [Vendor advisory]https://ubuntu.com/security/notices/USN-4917-1
- [Other]https://www.openwall.com/lists/oss-security/2021/04/16/2
- [Other]https://www.zerodayinitiative.com/advisories/ZDI-21-422/
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