CVE-2021-3492
Ubuntu linux kernel shiftfs file system double free vulnerability
HIGH 7.8EPSS 1.5%
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.
- Affected
- Ubuntu · Linux kernel
- CVSS v3.1 NVD
- 7.8 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS v3.1 UBUNTU
- 8.8 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - CVSS v2.0 NVD
- 7.2 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C - EPSS
- 1.54% chance of exploitation in the next 30 days, 74th percentile
- Published
- 2021-04-17
- Updated
- 2024-09-17
Proof-of-concept exploits (1)
- synacktiv/CVE-2021-349242★ · 2021-08-03
Security advisories
- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=25c89…
- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal/commit/?id=8fee5…
- https://ubuntu.com/security/notices/USN-4917-1
- http://packetstormsecurity.com/files/162614/Kernel-Live-Patch-Security-Notice-LSN-0077-1…
- https://www.openwall.com/lists/oss-security/2021/04/16/2
- https://www.zerodayinitiative.com/advisories/ZDI-21-422