According to recent reports, Cisco Firepower Management Center (FMC) software is affected by multiple vulnerabilities in its web-based management interface, which could allow an authenticated, remote attacker to perform a stored cross-site scripting (XSS) attack against a user of the interface. This vulnerability is identified as CVE-2022-20872.

The vulnerabilities are due to inadequate validation of user-supplied input by the web-based management interface, resulting in an opportunity for an attacker to exploit these vulnerabilities by injecting malicious input into various data fields in the affected interface. If exploited successfully, the attacker could execute arbitrary script code within the context of the interface or access sensitive browser-based information. In some cases, the attack may even cause temporary unavailability of specific sections of the FMC Dashboard.

Original References

- Cisco Security Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-stored-xss-gzYHzhQY
- National Vulnerability Database (NVD) Entry: https://nvd.nist.gov/vuln/detail/CVE-2022-20872

Code Snippet

This code snippet exemplifies a simple stored XSS payload that an attacker might use in their attempt to exploit the vulnerability:

<script>alert("Stored XSS Vulnerability: CVE-2022-20872")</script>

The attacker may insert this payload into various data fields in the FMC web-based management interface, causing the victim's browser to execute the script when the corresponding data field’s content is displayed.

Exploit Details

For a successful exploitation attempt, the attacker must first be authenticated, meaning they must have valid login credentials to FMC's web-based management interface. It is important to note that this is not a privilege escalation exploit, as the attacker can only execute the stored XSS payload within the context of their existing permissions.

Upon successful authentication, the attacker can then craft their payload and insert it into specific data fields found within the FMC web-based management interface. As mentioned earlier, the payload can cause arbitrary script execution, sensitive information exposure, or temporary unavailability of certain FMC Dashboard components.

Cisco has already released software updates to address these vulnerabilities. Therefore, it is highly recommended for all affected users to update their Cisco FMC software promptly to minimize the risk associated with these vulnerabilities.

To Summarize

CVE-2022-20872 highlights multiple vulnerabilities in the web-based management interface of Cisco Firepower Management Center (FMC) Software. Due to insufficient validation of user-supplied input, an authenticated, remote attacker can conduct stored XSS attacks against users of the affected device by inserting crafted input in several data fields. A successful exploitation could result in arbitrary script execution, exposure of sensitive browser-based information, and temporary unavailability of certain FMC Dashboard components. Users are advised to update their Cisco FMC software to the latest version immediately to mitigate the associated risks.

Timeline

Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/18/2022 18:13:00 UTC