CVEvulnerability

CVE-2023-20198

10.0 CRITICAL Known exploited Published 2023-10-16 Modified 2026-06-17 Official page ↗

CISA Known Exploited Vulnerability

Cisco IOS XE Web UI Privilege Escalation Vulnerability — Cisco IOS XE Web UI

Cisco IOS XE Web UI contains a privilege escalation vulnerability in the web user interface that could allow a remote, unauthenticated attacker to create an account with privilege level 15 access. The attacker can then use that account to gain control of the affected device.

Added to KEV: 2023-10-16
Remediation due: 2023-10-20
Ransomware use: Unknown
Required action: 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.
Notes: https://www.cisco.com/c/en/us/support/docs/ios-nx-os-software/ios-xe-dublin-17121/221128-software-fix-availability-for-cisco-ios.html; https://nvd.nist.gov/vuln/detail/CVE-2023-20198

Status: Analyzed
Published: 2023-10-16
Last modified: 2026-06-17
Assigner: [email protected]
CVSS 3.1 ([email protected]): 10.0 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS 3.1 ([email protected]): 10.0 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Weaknesses: CWE-420

Description

Cisco is providing an update for the ongoing investigation into observed exploitation of the web UI feature in Cisco IOS XE Software. We are updating the list of fixed releases and adding the Software Checker. Our investigation has determined that the actors exploited two previously unknown issues. The attacker first exploited CVE-2023-20198 to gain initial access and issued a privilege 15 command to create a local user and password combination. This allowed the user to log in with normal user access. The attacker then exploited another component of the web UI feature, leveraging the new local user to elevate privilege to root and write the implant to the file system. Cisco has assigned CVE-2023-20273 to this issue. CVE-2023-20198 has been assigned a CVSS Score of 10.0. CVE-2023-20273 has been assigned a CVSS Score of 7.2. Both of these CVEs are being tracked by CSCwh87343.

Affected configurations

• rockwellautomation allen-bradley stratix 5200 firmware (< 17.12.02) • rockwellautomation allen-bradley stratix 5800 firmware (< 17.12.02) • cisco ios xe (>= 16.12 < 16.12.10a) • cisco ios xe (>= 17.3 < 17.3.8a) • cisco ios xe (>= 17.6 < 17.6.6a) • cisco ios xe (>= 17.9 < 17.9.4a)

Weakness · CWE (1)

CWE-420 Unprotected Alternate Channel weakness

References