Cisco IOS XE SD-WAN Software Arbitrary File Corruption Vulnerability

Vulnerability

A vulnerability in the CLI of Cisco IOS XE SD-WAN Software allows an authenticated, local attacker to overwrite arbitrary files on the underlying file system. The issue stems from insufficient validation of parameters passed to a specific CLI command. Affected versions include Cisco IOS XE SD-WAN Software releases prior to the fixed versions detailed in Cisco Security Advisory cisco-sa-iosxe-arbfile-FUxskKDE [1].

Exploitation

An attacker must have authenticated local access to the device. The attacker can exploit the vulnerability by issuing the vulnerable CLI command with specially crafted parameters. No additional user interaction is required beyond authentication. The exact command and parameters are described in the advisory [1].

Impact

Successful exploitation allows the attacker to overwrite the content of any arbitrary file on the host file system. This can lead to denial of service, privilege escalation, or other impacts depending on the file overwritten. The attacker gains the ability to corrupt system or configuration files, potentially compromising device integrity and availability.

Mitigation

Cisco has released software updates that address this vulnerability. Customers should upgrade to the fixed versions listed in the advisory [1]. Cisco also provides the Cisco Software Checker tool to help determine exposure and identify the earliest fixed release. No workarounds are available. Users are advised to consult the advisory for complete details.