Cisco Expressway Gateways (Critical)

by jdpoteet | Feb 12, 2024 | Threat Advisories

Cisco Expressway Gateways (Critical)

SUMMARY

Cisco reported three vulnerabilities impacting its Expressway Series collaboration gateways, with two rated as critical severity and potentially exposing susceptible devices to cross-site request forgery (CSRF) attacks.

RISK SCORING

CVE-ID                           CVSSv3 Score

CVE-2024-20252            9.6

CVE-2024-20254            9.6

CVE-2024-20255            8.2

VULNERABILITY DETAILS

CSRF vulnerabilities can be exploited by attackers to deceive authenticated users into unwittingly initiating malicious actions. This includes activities like adding unauthorized user accounts, executing arbitrary code, acquiring administrative privileges, and other unauthorized actions, typically by enticing users to click on malicious links or visit attacker-controlled web pages.

CVE-2024-20252 and CVE-2024-20254:

Unauthenticated attackers can exploit the two critical CSRF vulnerabilities in Expressway gateways to target unpatched devices remotely. CVE-2024-20252 specifically targets gateways where the cluster database (CDB) API feature has been activated, limiting its exploitability to those configurations.  By convincing a user to click on a specially crafted link, attackers could execute arbitrary actions with the user’s privilege level. If the affected user has administrative privileges, this could result in modifying system configurations and creating new privileged accounts. Note: these vulnerabilities impact Cisco Expressway Series devices in their default configurations.

CVE-2024-20255:

The CSRF security vulnerability can also enable attackers to manipulate the configuration of vulnerable systems and induce denial of service conditions. CVE-2024-20252 specifically targets gateways where the cluster database (CDB) API feature has been activated, limiting its exploitability to those configurations.

AFFECTED PRODUCTS

• Expressway Series: 14.0 and older, 15.0
• Cisco TelePresence Video Communication Server: All versions

SOLUTIONS

• Update to Expressway Series: 14.3.4 and 15.0.0
• Cisco says it will not release security updates for the Cisco TelePresence Video Communication Server (VCS) gateway to address the three vulnerabilities since they have reached the end-of-support date on December 31, 2023.

REFERENCES

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-expressway-csrf-KnnZDMj3
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-expressway-csrf-KnnZDMj3#fs
• https://www.cybersecurity-help.cz/vdb/SB2024020839
• https://www.bleepingcomputer.com/news/security/critical-cisco-bug-exposes-expressway-gateways-to-csrf-attacks/
• https://bnnbreaking.com/tech/cisco-discloses-three-critical-csrf-vulnerabilities-in-expressway-series

Multiple Vulnerabilities in Ivanti Products Could Allow for Remote Code Execution

by jdpoteet | Feb 1, 2024 | Threat Advisories

Multiple Vulnerabilities in Ivanti Products Could Allow for Remote Code Execution

OVERVIEW

Multiple Vulnerabilities have been discovered in Ivanti Products, the most severe of which could allow for remote code execution.

• Ivanti Connect Secure is a SSL VPN solution for remote and mobile users.
• Ivanti Policy Secure (IPS) is a network access control (NAC) solution which provides network access only to authorized and secured users and devices.
• Ivanti Neurons for Zero Trust Access (nZTA) creates a secure connection from a device to web-based applications on-premises and in the cloud.

Successful exploitation could allow for remote code execution in the context of the system. Depending on the privileges associated with the logged-on user, an attacker could then install programs; view, change, or delete data. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

THREAT INTELLIGENCE

According to Ivanti, there have been reports of targeted exploitation of CVE-2024-21893. Ivanti, CISA, and other resources have reported widespread exploitation of CVE-2024-21887, and CVE-2023-46805.

SYSTEMS AFFECTED

• Ivanti Connect Secure (9.x, 22.x)
• Ivanti Policy Secure (9.x, 22.x)
• Ivanti Neurons for ZTA (9.x, 22.x)

RISK

Government:

• Large and medium government entities: High
• Small government entities: Medium

Businesses:

• Large and medium business entities: High
• Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY

Multiple Vulnerabilities have been discovered in Ivanti Products, the most severe of which could allow for remote code execution. Details of these vulnerabilities are as follows:

Tactic: Initial Access (TA0001):

Technique: Exploit Public-Facing Application (T1190):

• A command injection vulnerability in web components of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure allows an authenticated administrator to send specially crafted requests and execute arbitrary commands on the appliance. This vulnerability can be exploited over the internet. (CVE-2024-21887)
• An authentication bypass vulnerability in the web component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure allows a remote attacker to access restricted resources by bypassing control checks. (CVE-2023-46805)
• A server-side request forgery vulnerability in the SAML component of Ivanti Connect Secure (9.x, 22.x), Ivanti Policy Secure (9.x, 22.x) and Ivanti Neurons for ZTA allows an attacker to access certain restricted resources without authentication. (CVE-2024-21893)

Tactic: Privilege Escalation (TA0004):

Technique: Exploitation for Privilege Escalation (T1068):

• A privilege escalation vulnerability in web component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) allows a user to elevate privileges to that of an administrator. (CVE-2024-21888)

CVE-2023-46805 and CVE-2024-21887 can be chained to achieve remote code execution in the context of the system. Depending on the privileges associated with the logged-on user, an attacker could then install programs; view, change, or delete data. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

RECOMMENDATIONS

We recommend the following actions be taken:

• Apply appropriate updates provided by Ivanti to vulnerable systems immediately after appropriate testing. (M1051: Update Software)

• • Safeguard 7.1 : Establish and Maintain a Vulnerability Management Process: Establish and maintain a documented vulnerability management process for enterprise assets. Review and update documentation annually, or when significant enterprise changes occur that could impact this Safeguard.
  • Safeguard 7.2: Establish and Maintain a Remediation Process: Establish and maintain a risk-based remediation strategy documented in a remediation process, with monthly, or more frequent, reviews.
  • Safeguard 7.4: Perform Automated Application Patch Management: Perform application updates on enterprise assets through automated patch management on a monthly, or more frequent, basis.
  • Safeguard 7.5 : Perform Automated Vulnerability Scans of Internal Enterprise Assets: Perform automated vulnerability scans of internal enterprise assets on a quarterly, or more frequent, basis. Conduct both authenticated and unauthenticated scans, using a SCAP-compliant vulnerability scanning tool.
  • Safeguard 7.7: Remediate Detected Vulnerabilities: Remediate detected vulnerabilities in software through processes and tooling on a monthly, or more frequent, basis, based on the remediation process.
  • Safeguard 12.1: Ensure Network Infrastructure is Up-to-Date: Ensure network infrastructure is kept up-to-date. Example implementations include running the latest stable release of software and/or using currently supported network-as-a-service (NaaS) offerings. Review software versions monthly, or more frequently, to verify software support.
  • Safeguard 18.1: Establish and Maintain a Penetration Testing Program: Establish and maintain a penetration testing program appropriate to the size, complexity, and maturity of the enterprise. Penetration testing program characteristics include scope, such as network, web application, Application Programming Interface (API), hosted services, and physical premise controls; frequency; limitations, such as acceptable hours, and excluded attack types; point of contact information; remediation, such as how findings will be routed internally; and retrospective requirements.
  • Safeguard 18.2: Perform Periodic External Penetration Tests: Perform periodic external penetration tests based on program requirements, no less than annually. External penetration testing must include enterprise and environmental reconnaissance to detect exploitable information. Penetration testing requires specialized skills and experience and must be conducted through a qualified party. The testing may be clear box or opaque box.
  • Safeguard 18.3: Remediate Penetration Test Findings: Remediate penetration test findings based on the enterprise’s policy for remediation scope and prioritization.

• Apply the Principle of Least Privilege to all systems and services. Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack. (M1026: Privileged Account Management)

• • Safeguard 4.7: Manage Default Accounts on Enterprise Assets and Software: Manage default accounts on enterprise assets and software, such as root, administrator, and other pre-configured vendor accounts. Example implementations can include: disabling default accounts or making them unusable.
  • Safeguard 5.5: Establish and Maintain an Inventory of Service Accounts: Establish and maintain an inventory of service accounts. The inventory, at a minimum, must contain department owner, review date, and purpose. Perform service account reviews to validate that all active accounts are authorized, on a recurring schedule at a minimum quarterly, or more frequently.

• Vulnerability scanning is used to find potentially exploitable software vulnerabilities to remediate them. (M1016: Vulnerability Scanning)

• • Safeguard 16.13: Conduct Application Penetration Testing: Conduct application penetration testing. For critical applications, authenticated penetration testing is better suited to finding business logic vulnerabilities than code scanning and automated security testing. Penetration testing relies on the skill of the tester to manually manipulate an application as an authenticated and unauthenticated user.

• Architect sections of the network to isolate critical systems, functions, or resources. Use physical and logical segmentation to prevent access to potentially sensitive systems and information. Use a DMZ to contain any internet-facing services that should not be exposed from the internal network. Configure separate virtual private cloud (VPC) instances to isolate critical cloud systems. (M1030: Network Segmentation)

• • Safeguard 12.2: Establish and Maintain a Secure Network Architecture: Establish and maintain a secure network architecture. A secure network architecture must address segmentation, least privilege, and availability, at a minimum.

• Use capabilities to detect and block conditions that may lead to or be indicative of a software exploit occurring. (M1050: Exploit Protection)

• • Safeguard 10.5:  Enable Anti-Exploitation Features: Enable anti-exploitation features on enterprise assets and software, where possible, such as Microsoft® Data Execution Prevention (DEP), Windows® Defender Exploit Guard (WDEG), or Apple® System Integrity Protection (SIP) and Gatekeeper™.

REFERENCES

Ivanti:
https://forums.ivanti.com/s/article/KB-CVE-2023-46805-Authentication-Bypass-CVE-2024-21887-Command-Injection-for-Ivanti-Connect-Secure-and-Ivanti-Policy-Secure-Gateways?language=en_US
https://forums.ivanti.com/s/article/CVE-2024-21888-Privilege-Escalation-for-Ivanti-Connect-Secure-and-Ivanti-Policy-Secure?language=en_US

CVE:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-46805
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21887
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21888
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21893

Critical Cisco Flaw (CVE-2024-20253)

by jdpoteet | Jan 29, 2024 | Threat Advisories

Critical Cisco Flaw (CVE-2024-20253)

Summary

Cisco issued updates to address a severe security vulnerability affecting Unified Communications and Contact Center Solutions. This vulnerability is caused by improper handling of user input, potentially allowing remote code execution (RCE) on a targeted device by sending a specifically crafted message to a susceptible listening port.

CVE-2024-20253 | CVSS score of 9.9

Vulnerability Details

The Cisco advisory stated, “…a successful exploitation of the identified vulnerability could empower an attacker to execute arbitrary commands on the underlying operating system, utilizing the privileges of the web services user”. Once access to the device’s operating system is achieved, the attacker could establish root access on the compromised device.

Initially discovered by Julien Egloff from Synacktiv, the flaw was found to affect various Cisco products, including:

• Unified Communications Manager (versions 11.5, 12.5(1), and 14),
• Unified Communications Manager IM & Presence Service (versions 11.5(1), 12.5(1), and 14),
• Unified Communications Manager Session Management Edition (versions 11.5, 12.5(1), and 14),
• Unified Contact Center Express (versions 12.0 and earlier, and 12.5(1)),
• Unity Connection (versions 11.5(1), 12.5(1), and 14), and
• Virtualized Voice Browser (versions 12.0 and earlier, 12.5(1), and 12.5(2)).

While there are currently no workarounds available to mitigate the vulnerability, Cisco recommends users implement access control lists (ACLs) on intermediary devices. This precautionary measure aims to restrict access by allowing communication only to the ports of deployed services. Cisco emphasized the importance of this step, especially in situations where applying the provided updates may not be immediately feasible.

Recommendations

• Immediately apply the patches released by Cisco to address the security flaw.
• Implement access control lists (ACLs) on intermediary devices that separate the Cisco Unified Communications or Cisco Contact Center Solutions cluster from users and the broader network.
• Deploy network monitoring tools to actively monitor and analyze network traffic.

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-rce-bWNzQcUm
• https://thehackernews.com/2024/01/critical-cisco-flaw-lets-hackers.html