CVE-2023-20273

Vulnerability details

Cisco IOS XE contains a command injection vulnerability in the web user interface. When chained with CVE-2023-20198, the attacker can leverage the new local user to elevate privilege to root and write the implant to the file system. Cisco identified CVE-2023-20273 as the vulnerability exploited to deploy the implant. CVE-2021-1435, previously associated with the exploitation events, is no longer believed to be related to this activity.

Added to CISA KEV: 2023-10-23

Ransomware campaign use: Unknown

CISA due date: 2023-10-27

Defensive guidance from CISA

Verify that instances of Cisco IOS XE Web UI are in compliance with BOD 23-02 and apply mitigations per vendor instructions. For affected products (Cisco IOS XE Web UI exposed to the internet or to untrusted networks), follow vendor instructions to determine if a system may have been compromised and immediately report positive findings to CISA.

This is the source's required-action field, not an independently validated patch procedure. Refer to the vendor for exact affected versions and fixes.