CVE-2021-3493
Vulnerability from cvelistv5
Published
2021-04-17 04:20
Modified
2025-02-07 12:37
Severity ?
8.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
References
security@ubuntu.comhttp://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.htmlExploit, Third Party Advisory, VDB Entry
security@ubuntu.comhttp://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.htmlThird Party Advisory, VDB Entry
security@ubuntu.comhttp://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.htmlExploit, Third Party Advisory, VDB Entry
security@ubuntu.comhttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52Mailing List, Patch, Third Party Advisory
security@ubuntu.comhttps://ubuntu.com/security/notices/USN-4917-1Vendor Advisory
security@ubuntu.comhttps://www.openwall.com/lists/oss-security/2021/04/16/1Mailing List, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.htmlExploit, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.htmlThird Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.htmlExploit, Third Party Advisory, VDB Entry
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52Mailing List, Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://ubuntu.com/security/notices/USN-4917-1Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.openwall.com/lists/oss-security/2021/04/16/1Mailing List, Third Party Advisory
Impacted products
Vendor Product Version
Ubuntu linux kernel Version: 5.8 kernel   < 5.8.0-50.56
Version: 5.4 kernel   < 5.4.0-72.80
Version: 4.15 kernel   < 4.15.0-142.146
Version: 4.4 kernel   < 4.4.0-209.241
 Create a notification for this product.
CISA Known exploited vulnerability
Data from the Known Exploited Vulnerabilities Catalog

Date added: 2022-10-20

Due date: 2022-11-10

Required action: Apply updates per vendor instructions.

Used in ransomware: Unknown

Notes: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52; https://nvd.nist.gov/vuln/detail/CVE-2021-3493

Show details on NVD website

To clipboard 

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