Symlink Attack Affecting chrony package, versions [,3.5.1)


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.49% (38th percentile)

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  • Snyk IDSNYK-UNMANAGED-CHRONY-2371509
  • published26 Jan 2022
  • disclosed24 Aug 2020
  • creditUnknown

Introduced: 24 Aug 2020

CVE-2020-14367  (opens in a new tab)
CWE-59  (opens in a new tab)

How to fix?

Upgrade chrony to version 3.5.1 or higher.

Overview

Affected versions of this package are vulnerable to Symlink Attack. A flaw was found in chrony versions before 3.5.1 when creating the PID file under the /var/run/chrony folder. The file is created during chronyd startup while still running as the root user, and when it's opened for writing, chronyd does not check for an existing symbolic link with the same file name. This flaw allows an attacker with privileged access to create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service due to the path traversal.

CVSS Base Scores

version 3.1