Symlink Attack Affecting systemd/systemd package, versions [,237)


Severity

Recommended
0.0
high
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.06% (30th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-UNMANAGED-SYSTEMDSYSTEMD-2365465
  • published26 Jan 2022
  • disclosed29 Jan 2018
  • creditUnknown

Introduced: 29 Jan 2018

CVE-2017-18078  (opens in a new tab)
CWE-59  (opens in a new tab)

How to fix?

Upgrade systemd/systemd to version 237 or higher.

Overview

Affected versions of this package are vulnerable to Symlink Attack systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on hardlinked files even if the fs.protected_hardlinks sysctl is turned off, which allows local users to bypass intended access restrictions via vectors involving a hard link to a file for which the user lacks write access, as demonstrated by changing the ownership of the /etc/passwd file.

References

CVSS Scores

version 3.1