CVE-2017-18078

Advisory lineage Upstream: 0 Downstream: 5
Modified
Published: 29 Jan 2018, 05:00
Last modified:05 Aug 2024, 21:13

Vulnerability Summary

Overall Risk (default)
medium
41/100
CVSS Score
7.8 HIGH
v3.1 (nvd)
EPSS Score
0.08% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
4 found
Dark Web
Not detected

Timeline

29 Jan 2018, 05:00
Published
Vulnerability first disclosed
05 Aug 2024, 21:13
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

  • v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • v2.0•MEDIUM•Score: 4.6AV:L/AC:L/Au:N/C:P/I:P/A:P

EPSS Trends

Current EPSS score: 0.08%• Percentile: 25%

Techniques & Countermeasures

  • CWE-59•Improper Link Resolution Before File Access ('Link Following')

    The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Systems

  • debian•debian_linux

    8.0

  • opensuse•leap

    42.3

  • systemd_project•systemd

    < 237

References (9)