CVE-2023-20198

CRITICAL(10.0)KEVLikely Exploited

Cisco IOS XE Web UI Privilege Escalation Vulnerability

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.

KEV Information

Vendor
Cisco
Product
IOS XE Web UI
Date Added
October 16, 2023
Due Date
October 20, 2023
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.

CVSS Score

Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HOpen in Calculator
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
6.0

CWEs

Affected Products

VendorProductVersion
rockwellautomationallen-bradley stratix 5200 firmware< 17.12.02
rockwellautomationallen-bradley stratix 5800 firmware< 17.12.02
ciscoios xe>= 16.12, < 16.12.10a; >= 17.3, < 17.3.8a; >= 17.6, < 17.6.6a; >= 17.9, < 17.9.4a

Multiple CVSS Assessments

Source: [email protected](Secondary)
10.0
CRITICAL

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

Source: [email protected](Primary)
10.0
CRITICAL

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

References

CVSS Score

10.0
CRITICAL(10.0)

EPSS Score

EPSS Score99.57%
EPSS Percentile99.9%

Dates

PublishedOctober 16, 2023
Last ModifiedJune 17, 2026
StatusAnalyzed
CVSS Versionv3.1

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