Cisco Firepower Management Center (FMC) Software has multiple vulnerabilities within the web-based management interface that can potentially grant an authenticated, remote attacker the ability to execute a stored cross-site scripting (XSS) attack against a user operating on an affected device. These vulnerabilities stem from inadequate validation of user-supplied input by the web-based management interface. A hacker could exploit these vulnerabilities by inputting crafted data within multiple data fields in the affected interface, potentially granting them the ability to execute arbitrary script code within the interface's context or gain access to sensitive, browser-based information. In some instances, this issue can lead to a temporary availability impact on parts of the FMC Dashboard.

Overview of CVE-2022-20835 Vulnerabilities

Cisco FMC Software has been found to contain vulnerabilities that could expose users to a risk of stored XSS attacks. These vulnerabilities originate from insufficient validation of user-supplied input by the web-based management interface. An attacker could exploit these vulnerabilities by injecting malicious input into various data fields in an affected interface. To be successful, the attacker must be authenticated in the FMC system.

When exploited, these vulnerabilities could facilitate an attacker to execute arbitrary script code in the context of the interface or access sensitive data on the victim's browser. Under specific circumstances, this vulnerability could also lead to temporary outages within elements of the FMC Dashboard.

Code Snippet

An example of a possible exploit conducted by an attacker could involve inputting malicious JavaScript code into a vulnerable input field, such as:

<script>alert('XSS ATTACK');</script>

When a user interacts with the compromised input field, the injected script is executed, displaying an alert box with the text "XSS ATTACK".

Exploit Details

The following steps outline the process an attacker might take to exploit the vulnerabilities related to CVE-2022-20835:

Wait for the targeted user to interact with the affected interface element.

5. Once the user interacts with the compromised input field, the attacker's script is executed, potentially allowing them to execute arbitrary code, access sensitive data, or cause temporary unavailability in parts of the FMC Dashboard.

For more information on this vulnerability and its patches, explore the following resources

- Cisco Firepower Management Center (FMC) Software Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-store-xss-YzczdfWy
- Cisco Bug Search Tool: https://bst.cloudapps.cisco.com/bugsearch/search?kw=CVE-2022-20835
- NIST National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2022-20835

Mitigation

To mitigate the risks associated with CVE-2022-20835, Cisco has released software updates that address these vulnerabilities. Users of Cisco FMC Software should promptly install the necessary patches as directed by the Cisco Security Advisory to safeguard their systems from exploitation by attackers.

Conclusion

The multiple vulnerabilities in the Cisco Firepower Management Center (FMC) Software's web-based management interface can expose users to stored cross-site scripting (XSS) attacks, unauthorized script execution, and potential downtime of dashboard components. It is crucial for organizations relying on Cisco FMC Software to apply the provided security updates promptly and maintain a proactive approach to protecting their systems against emerging cybersecurity threats.

Timeline

Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/18/2022 18:14:00 UTC