CVE-2020-11933 local snapd exploit through cloud-init

2020-07-2916:25:25

CWE-264

canonical

www.cve.org

cve-2020-11933

snapd exploit

cloud-init

ubuntu core

full disk encryption

CVSS3

7.3

Attack Vector

PHYSICAL

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

NONE

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

AI Score

Confidence

High

EPSS

0.001

Percentile

29.4%

JSON

cloud-init as managed by snapd on Ubuntu Core 16 and Ubuntu Core 18 devices was run without restrictions on every boot, which a physical attacker could exploit by crafting cloud-init user-data/meta-data via external media to perform arbitrary changes on the device to bypass intended security mechanisms such as full disk encryption. This issue did not affect traditional Ubuntu systems. Fixed in snapd version 2.45.2, revision 8539 and core version 2.45.2, revision 9659.

CNA Affected

[
  {
    "product": "snapd",
    "vendor": "Canonical",
    "versions": [
      {
        "lessThan": "2.45.2, revision 8539",
        "status": "affected",
        "version": "2.45.2",
        "versionType": "custom"
      }
    ]
  },
  {
    "product": "core",
    "vendor": "Canonical",
    "versions": [
      {
        "lessThan": "2.45.2, revision 9659",
        "status": "affected",
        "version": "2.45.2",
        "versionType": "custom"
      }
    ]
  }
]