CVE-2021-3493
HIGH
8,8
Source: [email protected]
Attack Vector: local
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: changed
Confidentiality: high
Integrity: high
Availability: high
HIGH
7,2
Source: [email protected]
Access Vector: local
Access Complexity: low
Authentication: none
Confidentiality: complete
Integrity: complete
Availability: complete
Description
AI Translation Available
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.
EPSS (Exploit Prediction Scoring System)
Trend Analysis
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.
EPSS Score
0,7825
Percentile
1,0th
Updated
EPSS Score Trend (Last 90 Days)
270
Privilege Context Switching Error
DraftCommon Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Gain Privileges Or Assume Identity
Applicable Platforms
All platforms may be affected
863
Incorrect Authorization
IncompleteCommon Consequences
Security Scopes Affected:
Confidentiality
Integrity
Access Control
Availability
Potential Impacts:
Read Application Data
Read Files Or Directories
Modify Application Data
Modify Files Or Directories
Gain Privileges Or Assume Identity
Bypass Protection Mechanism
Execute Unauthorized Code Or Commands
Dos: Crash, Exit, Or Restart
Dos: Resource Consumption (Cpu)
Dos: Resource Consumption (Memory)
Dos: Resource Consumption (Other)
Applicable Platforms
Technologies:
Database Server, Not Technology-Specific, Web Server
Operating System
Ubuntu Linux by Canonical
Version Range Affected
From
18.04.1
(inclusive)
To
20.04
(exclusive)
CPE Identifier
View Detailed Analysis
cpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:lts:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System
Ubuntu Linux by Canonical
Version Range Affected
To
18.04
(exclusive)
CPE Identifier
View Detailed Analysis
cpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:lts:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
Operating System
Ubuntu Linux by Canonical
Version Range Affected
To
20.10
(exclusive)
CPE Identifier
View Detailed Analysis
cpe:2.3:o:canonical:ubuntu_linux:*:*:*:*:-:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021…
http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-L…
http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Es…
http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Es…
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7…
https://ubuntu.com/security/notices/USN-4917-1
https://www.openwall.com/lists/oss-security/2021/04/16/1
http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-L…
http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Es…
http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Es…
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7…
https://ubuntu.com/security/notices/USN-4917-1
https://www.openwall.com/lists/oss-security/2021/04/16/1