CVE-2023-1314: cloudflare cloudflared Link Following

Vulnerability summary

CVE-2023-1314 is a high (CVSS 7.8) Link Following vulnerability in cloudflare cloudflared. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.5% of scored vulnerabilities.

Timeline

1. 21-03-2023
   PublishedVulnerability first disclosed.
2. 26-02-2025
   Last modifiedVulnerability information updated.

Description

A vulnerability has been discovered in cloudflared's installer (<= 2023.3.0) for Windows 32-bits devices that allows a local attacker with no administrative permissions to escalate their privileges on the affected device. This vulnerability exists because the MSI installer used by cloudflared relied on a world-writable directory. An attacker with local access to the device (without Administrator rights) can use symbolic links to trick the MSI installer into deleting files in locations that the attacker would otherwise have no access to. By creating a symlink from the world-writable directory to the target file, the attacker can manipulate the MSI installer's repair functionality to delete the target file during the repair process. Exploitation of this vulnerability could allow an attacker to delete important system files or replace them with malicious files, potentially leading to the affected device being compromised. The cloudflared client itself is not affected by this vulnerability, only the installer for 32-bit Windows devices.

• CWE-59Improper 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.