Zero-day vulnerability in Phone Apps

Input validation error
CVE-2021-45461

Vulnerability details

Advisory: SB2021122228 - Remote code execution in FreePBX Phone Apps module

Vulnerable component: Phone Apps

CVE-ID: CVE-2021-45461

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-20 - Improper input validation

Description:

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to insufficient validation of user-supplied input in the Phone Apps (restapps) module for FreePBX. A remote attacker can send specially crafted input to the application and execute arbitrary code on the system.

Note, the vulnerability is being actively exploited in the wild.

External links:

https://community.freepbx.org/t/security-issue-potential-rest-phone-apps-rce/80109 https://wiki.freepbx.org/display/FOP/2021-12-21+SECURITY%3A+Potential+Rest+Phone+Apps+RCE https://community.freepbx.org/t/0-day-freepbx-exploit/80092

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.