Headline
CVE-2023-20241: Cisco Security Advisory: Cisco Secure Client Software Denial of Service Vulnerabilities
Multiple vulnerabilities in Cisco Secure Client Software, formerly AnyConnect Secure Mobility Client, could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. These vulnerabilities are due to an out-of-bounds memory read from Cisco Secure Client Software. An attacker could exploit these vulnerabilities by logging in to an affected device at the same time that another user is accessing Cisco Secure Client on the same system, and then sending crafted packets to a port on that local host. A successful exploit could allow the attacker to crash the VPN Agent service, causing it to be unavailable to all users of the system. To exploit these vulnerabilities, the attacker must have valid credentials on a multi-user system.
When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories page, to determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
Fixed Releases
At the time of publication, the release information in the following table was accurate. See the Details section in the bug ID(s) at the top of this advisory for the most complete and current information.
The left column lists Cisco software releases, and the center and right columns indicate whether a release was affected by the vulnerabilities that are described in this advisory and which release included the fix for these vulnerabilities.
Cisco Secure Client Software Release
First Fixed Release for CSCwf21381
First Fixed Release for CSCwf92553
4.10 and earlier1
4.10 MR8 (Dec 2023)
4.10 MR8 (Dec 2023)
5.0
5.0 MR4 (5.0.04032)
5.0 MR5 (5.0.05040)
5.1
Not vulnerable
Not vulnerable
1. Cisco Secure Client Software releases 4.10 and earlier were known as Cisco AnyConnect Secure Mobility Client.
The Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory.