CVE-2021-34718

A vulnerability in the SSH Server process of Cisco IOS XR Software could allow an authenticated, remote attacker to overwrite and read arbitrary files on the local device. This vulnerability is due to insufficient input validation of arguments that are supplied by the user for a specific file transfer method. An attacker with lower-level privileges could exploit this vulnerability by specifying Secure Copy Protocol (SCP) parameters when authenticating to a device. A successful exploit could allow the attacker to elevate their privileges and retrieve and upload files on a device that they should not have access to. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the September 2021 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2021 Cisco IOS XR Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74637"].