CVE-2021-3493

2021-04-1500:00:00

CWE-270

canonical

www.cve.org

8.8 High

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

8.2 High

AI Score

Confidence

High

0.006 Low

EPSS

Percentile

78.3%

JSON

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.

CNA Affected

[
  {
    "product": "linux kernel",
    "vendor": "Ubuntu",
    "versions": [
      {
        "lessThan": "5.8.0-50.56 ",
        "status": "affected",
        "version": "5.8 kernel",
        "versionType": "custom"
      },
      {
        "lessThan": " 5.4.0-72.80 ",
        "status": "affected",
        "version": "5.4 kernel",
        "versionType": "custom"
      },
      {
        "lessThan": "4.15.0-142.146 ",
        "status": "affected",
        "version": "4.15 kernel",
        "versionType": "custom"
      },
      {
        "lessThan": " 4.4.0-209.241",
        "status": "affected",
        "version": "4.4 kernel",
        "versionType": "custom"
      }
    ]
  }
]