CVE-2021-27256 Information

Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Although authentication is required to exploit this vulnerability the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the rc_service parameter provided to apply_save.cgi. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12355.

CVSS Vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://www.zerodayinitiative.com/advisories/ZDI-21-262/ https://kb.netgear.com/000062883/Security-Advisory-for-Multiple-Vulnerabilities-on-Some-Routers-Satellites-and-Extenders

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

8.8