Secure Client (AnyConnect)
CVE-2024-20474: A vulnerability in Internet Key Exchange version 2 (IKEv2) processing of Cisco Secure Client Software could…
A vulnerability in Internet Key Exchange version 2 (IKEv2) processing of Cisco Secure Client Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) of Cisco Secure Client.
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 Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.9 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 4.10 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.0 | See the advisory |
| Cisco Secure Client 5.1 | See the advisory |
| Cisco Secure Client 5.1 | See the advisory |
| Cisco Secure Client 5.1 | See the advisory |
| Cisco Secure Client 5.1 | See the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A vulnerability in Internet Key Exchange version 2 (IKEv2) processing of Cisco Secure Client Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) of Cisco Secure Client. This vulnerability is due to an integer underflow condition. An attacker could exploit this vulnerability by sending a crafted IKEv2 packet to an affected system. A successful exploit could allow the attacker to cause Cisco Secure Client Software to crash, resulting in a DoS condition on the client software. Note: Cisco Secure Client Software releases 4.10 and earlier were known as Cisco AnyConnect Secure Mobility Client.
Exploitation
The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.