CVE Vulnerabilities

CVE-2018-6198

Improper Link Resolution Before File Access ('Link Following')

Published: Jan 25, 2018 | Modified: Dec 29, 2023
CVSS 3.x
4.7
MEDIUM
Source:
NVD
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS 2.x
3.3 LOW
AV:L/AC:M/Au:N/C:N/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

w3m through 0.5.3 does not properly handle temporary files when the ~/.w3m directory is unwritable, which allows a local attacker to craft a symlink attack to overwrite arbitrary files.

Weakness

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 Software

Name Vendor Start Version End Version
W3m Tats * 0.5.3 (including)

Potential Mitigations

  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

References