UBUNTU-CVE-2017-18078

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 29 Jan 2018, 05:29
Last modified:22 Apr 2026, 11:21

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

29 Jan 2018, 05:29
Published
Vulnerability first disclosed
22 Apr 2026, 11:21
Last Modified
Vulnerability information updated

Description

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.

CVSS Metrics

  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • v3.0HIGHScore: 7.8CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • ubuntusystemd

    all

References (2)