CVE-2020-3556 Cisco AnyConnect Secure Mobility Client Arbitrary Code Execution Vulnerability
An authenticated local attacker can execute arbitrary code by sending crafted messages to the unauthenticated IPC listener of the Cisco AnyConnect client.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2020-3556?
CVE-2020-3556 is a high-severity missing authorization vulnerability in Cisco Anyconnect Secure Mobility Client, published on 6 Nov 2020. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client Software could allow an authenticated, local attacker to cause a targeted AnyConnect user to execute a malicious script. The vulnerability is due to a lack of authentication to the IPC listener. An attacker could exploit this vulnerability by sending crafted IPC messages to the AnyConnect client IPC listener. A successful exploit could allow an attacker to cause the targeted AnyConnect user to execute a script. This script would execute with the privileges of the targeted AnyConnect user. In order to successfully exploit this vulnerability, there must be an ongoing AnyConnect session by the targeted user at the time of the attack. To exploit this vulnerability, the attacker would also need valid user credentials on the system upon which the AnyConnect client is being run. Cisco has not released software updates that address this vulnerability.
Weakness: CWE-20
Which versions are affected by CVE-2020-3556?
It affects 1 product.
Products include Cisco Anyconnect Secure Mobility Client.
How do I fix CVE-2020-3556?
No fix has been published for CVE-2020-3556 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2020-3556 being exploited?
There is no known exploitation of CVE-2020-3556 in the wild and no public exploit code.
Other vulnerabilities in Cisco Anyconnect Secure Mobility Client
Sources
Also known as GHSA-v6p8-gw74-vfg4.