CVE Vulnerabilities

CVE-2021-1145

UNIX Symbolic Link (Symlink) Following

Published: Jan 13, 2021 | Modified: Nov 21, 2024
CVSS 3.x
6.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
4 MEDIUM
AV:N/AC:L/Au:S/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability in the Secure FTP (SFTP) of Cisco StarOS for Cisco ASR 5000 Series Routers could allow an authenticated, remote attacker to read arbitrary files on an affected device. To exploit this vulnerability, the attacker would need to have valid credentials on the affected device. The vulnerability is due to insecure handling of symbolic links. An attacker could exploit this vulnerability by sending a crafted SFTP command to an affected device. A successful exploit could allow the attacker to read arbitrary files on the affected device.

Weakness

The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files.

Affected Software

Name Vendor Start Version End Version
Staros Cisco * 21.19.7 (excluding)

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