A Closer Look at Cisco ISE Vulnerabilities

What are some recent Cisco ISE vulnerabilities?

Recent vulnerabilities in Cisco’s Identity Services Engine (ISE) include a variety of security issues that range from cross-site scripting (XSS) attacks to privilege escalation vulnerabilities. Here are some of the key vulnerabilities identified:

  1. CVE-2022-20964, CVE-2022-20966, and CVE-2022-20967: These vulnerabilities were related to cross-site scripting (XSS) and access bypass issues, which could allow an authenticated, remote attacker to inject arbitrary operating system commands, bypass security protections, or conduct cross-site scripting attacks​​.
  2. CVE-2023-20193 and CVE-2023-20194: These vulnerabilities targeted privilege escalation, affecting devices running vulnerable releases of Cisco ISE with specific features enabled, such as the Embedded Service Router (ESR) and External RESTful Services (ERS). Exploitation could allow authenticated, local attackers to read, write, or delete arbitrary files on the underlying operating system or escalate their privileges to root​​.
  3. CVE-2023-20272 and CVE-2023-20208: These issues included an arbitrary file write vulnerability and another XSS vulnerability. The arbitrary file write vulnerability could allow an authenticated, remote attacker to upload malicious files to the web root of the application, whereas the XSS vulnerability could allow an authenticated, remote attacker to conduct an XSS attack against a user of the web-based management interface​​.

For these vulnerabilities, Cisco has released software updates that address the issues, with no workarounds available. The vulnerabilities impact various versions of Cisco ISE, and users are encouraged to upgrade their systems to the patched versions as outlined in Cisco’s advisories.

How serious are some of the recent Cisco ISE vulnerabilities?

The seriousness of the most recent Cisco ISE vulnerabilities varies, but several have been classified with a “Medium” or “High” Security Impact Rating (SIR), indicating that they pose a significant risk if exploited. The Common Vulnerability Scoring System (CVSS) scores, which range from 0 to 10, provide a quantitative measure of the severity of the vulnerabilities. Here’s a breakdown of the severity of some of these vulnerabilities based on their CVSS scores and SIR:

  1. CVE-2022-20964: With a CVSS score of 6.3 and a High SIR, this vulnerability is significant due to its potential impact on confidentiality, integrity, and availability​​.
  2. CVE-2022-20966: This XSS vulnerability has a Medium SIR and a CVSS score of 5.4, indicating a moderate risk, particularly due to its potential for script or HTML injection​​.
  3. CVE-2022-20967: Also with a Medium SIR, this vulnerability has a slightly lower CVSS score of 4.8, reflecting its specific conditions for exploitation and potential impact​​.
  4. CVE-2023-20193 and CVE-2023-20194: Both privilege escalation vulnerabilities have Medium SIRs, with CVE-2023-20193 having a CVSS score of 6.0, indicating a potential for significant impact if exploited by an attacker with administrator-level privileges​​. CVE-2023-20194 has a CVSS score of 4.9, suggesting a lower but still noteworthy risk​​.
  5. CVE-2023-20272: This arbitrary file write vulnerability has a Medium SIR and a CVSS score of 6.7, indicating a substantial risk due to the potential for attackers to upload malicious files and gain access to sensitive server-side information​​.
  6. CVE-2023-20208: Another XSS vulnerability with a Medium SIR and a CVSS score of 4.8, which points to a moderate risk under specific conditions requiring administrative credentials for exploitation​​.

The severity of these vulnerabilities highlights the importance of applying the available software updates provided by Cisco to mitigate the risks. There are no workarounds for these vulnerabilities, making the application of updates critical for maintaining the security of affected systems. Regularly consulting Cisco advisories and ensuring systems are up to date with the latest security patches are key steps in protecting against these vulnerabilities.

Which Cisco ISE vulnerabilities have been successfully exploited?

Some of the most recent Cisco ISE vulnerabilities, particularly CVE-2022-20964, could be combined with others like CVE-2022-20959 to execute a one-click exploit that would allow attackers to gain root access to the system. This chain of vulnerabilities demonstrates the potential for significant exploitation, requiring attackers to have valid user credentials within the ISE system. Cisco has planned patches for these vulnerabilities, emphasizing the need for system administrators to apply updates promptly to mitigate risks​​.

How does Cisco’s support team typically help to resolve Cisco ISE vulnerabilities?

Cisco’s support team takes a structured approach to help resolve vulnerabilities in products like Cisco ISE. Their support typically involves the following steps:

  1. Vulnerability Identification and Documentation: Cisco often identifies vulnerabilities through internal testing, external security research, or customer reports. These vulnerabilities are then documented in detailed security advisories that are made publicly available. These advisories provide comprehensive information about the vulnerabilities, including descriptions, impact ratings, CVSS scores, and affected products​​​​​​.
  2. Software Updates and Fixes: For each identified vulnerability, Cisco’s team works on developing software updates or patches to mitigate the vulnerabilities. These fixes are then released and detailed in the security advisories, specifying the versions of software that address the vulnerabilities. Instructions for applying these updates are also provided to ensure that customers can secure their systems effectively​​​​​​.
  3. No Workaround Policy: In cases where no workaround is available for a vulnerability, Cisco stresses the importance of applying the software updates to mitigate risk. The advisories explicitly state when no workarounds exist, highlighting the necessity of updating the affected systems​​​​​​.
  4. Fixed Software and Upgrade Guidance: Cisco’s advisories include a “Fixed Software” section, which lists the first fixed releases available for affected software versions. This section is critical for customers in determining which software version to upgrade to in order to resolve the vulnerabilities. Additionally, Cisco provides upgrade guides and resources on their support page to assist customers in the upgrade process​​​​.
  5. Customer Support and Technical Assistance: For customers who need help or have questions regarding the vulnerabilities and the upgrading process, Cisco offers support through the Cisco Technical Assistance Center (TAC). Customers can contact TAC for personalized assistance, ensuring that they receive the help needed to address and mitigate the vulnerabilities effectively.
  6. Regular Communication and Updates: Cisco regularly updates its advisories and support documentation to reflect the latest information about vulnerabilities and their fixes. Customers are encouraged to consult these advisories regularly and subscribe to Cisco’s security notification service to stay informed about new vulnerabilities and updates.