CVE Vulnerabilities

CVE-2015-5700

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

Published: Aug 25, 2017 | Modified: Oct 12, 2018
CVSS 3.x
6.1
MEDIUM
Source:
NVD
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
CVSS 2.x
5.6 MEDIUM
AV:L/AC:L/Au:N/C:P/I:C/A:N
RedHat/V2
2.1 LOW
AV:L/AC:L/Au:N/C:N/I:P/A:N
RedHat/V3
Ubuntu
LOW

mktexlsr revision 22855 through revision 36625 as packaged in texlive allows local users to write to arbitrary files via a symlink attack.

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
Texlive Tug 20100722 (including) 20100722 (including)
Texlive Tug 20110705 (including) 20110705 (including)
Texlive Tug 20120701 (including) 20120701 (including)
Texlive Tug 20130530 (including) 20130530 (including)
Texlive Tug 20140525 (including) 20140525 (including)
Texlive-bin Ubuntu trusty *
Texlive-bin Ubuntu upstream *

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