Identity Services Engine
CVE-2023-20213: A vulnerability in the CDP processing feature of Cisco ISE could allow an unauthenticated, adjacent attacke…
A vulnerability in the CDP processing feature of Cisco ISE could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition of the CDP process on an affected device.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.6 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 2.7 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.0 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.1 | See the advisory |
| Cisco Identity Services Engine Software 3.2 | See the advisory |
| Cisco Identity Services Engine Software 3.2 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in the CDP processing feature of Cisco ISE could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition of the CDP process on an affected device. This vulnerability is due to insufficient bounds checking when an affected device processes CDP traffic. An attacker could exploit this vulnerability by sending crafted CDP traffic to the device. A successful exploit could cause the CDP process to crash, impacting neighbor discovery and the ability of Cisco ISE to determine the reachability of remote devices. After a crash, the CDP process must be manually restarted using the cdp enable command in interface configuration mode.
Exploitation
The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.