CVE-2022-20867 - An In-Depth Analysis of the Cisco Email Security Appliance SQL Injection Vulnerability

A critical security vulnerability, identified as CVE-2022-20867, was recently disclosed in the web-based management interface of the Cisco Email Security Appliance (ESA) and Cisco Secure Email and Web Manager (SEWM). This vulnerability allows an authenticated, remote attacker with high-privileged user credentials to perform SQL injection attacks as root on an affected system. This could potentially lead to unauthorized access and manipulation of sensitive data stored in the underlying database.

This post will provide an in-depth analysis of CVE-2022-20867, including code snippets, links to original references, and exploit details. The intention is to help security professionals and system administrators better understand this vulnerability, its potential impacts, and the steps needed to mitigate it.

Vulnerability Details

The main cause of the vulnerability is improper validation of user-submitted parameters within the web-based management interface of the affected Cisco Email Security Appliance and Cisco Secure Email and Web Manager. By exploiting this weakness, an attacker could achieve unauthorized access to the system's underlying database, enabling them to obtain or modify sensitive data.

Exploit Details

An attacker could exploit CVE-2022-20867 by first authenticating themselves using high-privileged user credentials, allowing them to access the application. They can then craft malicious requests to the affected system, triggering the SQL injection vulnerability.

To illustrate the exploit, consider the following code snippet

POST /path/to/vulnerable/endpoint HTTP/1.1
...
param1=example&param2=');SQL_INJECTION_HERE;--

In this example, the attacker has inserted an SQL injection payload into the HTTP POST request. Once executed, it may lead to unauthorized access to the vulnerable system's database, which can have serious consequences, such as the exfiltration or manipulation of sensitive data.

Mitigation and Solutions

To protect systems against CVE-2022-20867, Cisco has released software updates that address this vulnerability. Administrators are strongly encouraged to apply these updates immediately. Detailed instructions can be found in the official Cisco Security Advisory [1].

As a general best practice, it is also recommended to limit access to web-based management interfaces through the use of VPNs and network segmentation, as well as enforcing strict authentication and authorization controls.

Conclusion

CVE-2022-20867 is a serious vulnerability that demonstrates the potential dangers of failing to properly validate user-submitted parameters in web applications. By understanding the details of this exploit, security professionals and system administrators can take the necessary steps to secure their Cisco Email Security Appliance and Cisco Secure Email and Web Manager deployments against this threat. It is crucial to maintain vigilant patch management and follow security best practices to reduce the likelihood of being affected by similar vulnerabilities in the future.

Original References

[1] Cisco Security Advisory: "Cisco Email Security Appliance and Cisco Secure Email and Web Manager SQL Injection Vulnerability"
Link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cesa-sql-inj-G6bmyVGj

Timeline

Published on: 11/04/2022 18:15:00 UTC
Last modified on: 11/08/2022 14:44:00 UTC