#VU92413 Incorrect authorization in Linux kernel - CVE-2021-3493
Published: April 17, 2021 / Updated: June 21, 2024
Vulnerability identifier: #VU92413
Vulnerability risk: Low
CVSSv4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Clear
CVE-ID: CVE-2021-3493
CWE-ID: CWE-863
Exploitation vector: Local access
Exploit availability:
The vulnerability is being exploited in the wild
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a local user to execute arbitrary code.
The vulnerability exists due to incorrect authorization error within the validheader() and cap_convert_nscap() functions in security/commoncap.c, within the vfs_setxattr() and setxattr() functions in fs/xattr.c. A local user can execute arbitrary code.
Remediation
Install update from vendor's repository.
External links
- https://www.openwall.com/lists/oss-security/2021/04/16/1
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52
- https://ubuntu.com/security/notices/USN-4917-1
- http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html
- http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html
- http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html