CVE-2020-16123 Bypass of snapd pulseaudio restrictions

2020-11-2300:00:00

CWE-362

canonical

www.cve.org

cve-2020-16123

pulseaudio

ubuntu-specific

race condition

snap policy module

client connection

scm_credentials

exploit

sensitive information

patch

fixed

CVSS3

4.4

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

NONE

Availability Impact

NONE

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

AI Score

4.5

Confidence

High

EPSS

0.001

Percentile

18.0%

JSON

An Ubuntu-specific patch in PulseAudio created a race condition where the snap policy module would fail to identify a client connection from a snap as coming from a snap if SCM_CREDENTIALS were missing, allowing the snap to connect to PulseAudio without proper confinement. This could be exploited by an attacker to expose sensitive information. Fixed in 1:13.99.3-1ubuntu2, 1:13.99.2-1ubuntu2.1, 1:13.99.1-1ubuntu3.8, 1:11.1-1ubuntu7.11, and 1:8.0-0ubuntu3.15.

CNA Affected

[
  {
    "product": "pulseaudio",
    "vendor": "Canonical",
    "versions": [
      {
        "lessThan": "1:13.99.3-1ubuntu2",
        "status": "affected",
        "version": "1:13.99.3-1",
        "versionType": "custom"
      },
      {
        "lessThan": "1:13.99.2-1ubuntu2.1",
        "status": "affected",
        "version": "1:13.99.2-1",
        "versionType": "custom"
      },
      {
        "lessThan": "1:13.99.1-1ubuntu3.8",
        "status": "affected",
        "version": "1:13.99.1-1",
        "versionType": "custom"
      },
      {
        "lessThan": "1:11.1-1ubuntu7.11",
        "status": "affected",
        "version": "1:11.1-1",
        "versionType": "custom"
      },
      {
        "lessThan": "1:8.0-0ubuntu3.15",
        "status": "affected",
        "version": "1:8.0-0",
        "versionType": "custom"
      }
    ]
  }
]