CVE Vulnerabilities

CVE-2020-5797

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

Published: Nov 21, 2020 | Modified: Dec 03, 2020
CVSS 3.x
6.1
MEDIUM
Source:
NVD
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS 2.x
3.6 LOW
AV:L/AC:L/Au:N/C:P/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

UNIX Symbolic Link (Symlink) Following in TP-Link Archer C9(US)_V1_180125 firmware allows an unauthenticated actor, with physical access and network access, to read sensitive files and write to a limited set of files after plugging a crafted USB drive into the router.

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
Archer_c9_firmware Tp-link 180125 (including) 180125 (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