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CVE coverage

CVE-2023-20198

CVSS 10.0 Actively exploited (KEV) 4 detections found
View on NVD →
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.

Detection rules

Source Rule Status Updated
suricata ET MALWARE BadCandy Cisco IOS XE Implant Check-in rev 3 2026-10-21
snort ET TROJAN BadCandy Cisco IOS XE Implant Check-in rev 3 2026-10-21
splunk Cisco IOS XE Implant Access production 2026-05-13
sigma Exploitation Indicators Of CVE-2023-20198 test 2023-10-20