CVE-2020-7032 in WebLM
Summary
by MITRE • 11/13/2020
An XML external entity (XXE) vulnerability in Avaya WebLM admin interface allows authenticated users to read arbitrary files or conduct server-side request forgery (SSRF) attacks via a crafted DTD in an XML request. Affected versions of Avaya WebLM include: 7.0 through 7.1.3.6 and 8.0 through 8.1.2.
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Analysis
by VulDB Data Team • 12/07/2020
The CVE-2020-7032 vulnerability represents a critical xml external entity xxe flaw within the avaya weblm administrative interface that fundamentally undermines the security posture of affected systems. This vulnerability specifically targets versions 7.0 through 7.1.3.6 and 8.0 through 8.1.2 of the avaya weblm software, creating a pathway for authenticated attackers to exploit the system through carefully crafted xml requests. The flaw manifests when the system processes xml data containing external entity declarations without proper validation, allowing malicious actors to manipulate the xml parser behavior. The vulnerability operates through the use of crafted dtd files that can be embedded within xml requests, leveraging the xml parser's capability to resolve external entities and reference remote resources.
The technical exploitation of this vulnerability enables attackers to perform two primary malicious activities that significantly impact system security and data integrity. First, authenticated users can leverage the xxe vulnerability to read arbitrary files from the server filesystem, potentially accessing sensitive configuration files, user credentials, or other confidential data stored on the system. Second, the vulnerability facilitates server-side request forgery attacks, allowing attackers to make unauthorized requests to internal services or external systems that the vulnerable server can access. This dual capability makes the vulnerability particularly dangerous as it combines local file disclosure with network-based attack vectors. The vulnerability maps directly to cwe-611 (improper restriction of xml external entity reference) and falls under the broader category of xml injection attacks that have been extensively documented in cybersecurity frameworks. From an attack perspective, this vulnerability aligns with techniques described in the mitre att&ck framework under the initial access and privilege escalation phases, specifically targeting the exploitation of xml parsing vulnerabilities to gain unauthorized system access.
The operational impact of CVE-2020-7032 extends beyond immediate data exposure to encompass potential system compromise and lateral movement within network environments. Organizations running affected avaya weblm versions face significant risk of unauthorized data access, as attackers can bypass traditional access controls to retrieve sensitive information from within the organization's network perimeter. The server-side request forgery capability introduces additional risk by enabling attackers to probe internal network services, potentially identifying other vulnerable systems or conducting reconnaissance activities that could lead to more extensive compromise. Furthermore, the vulnerability's authentication requirement means that attackers must first establish valid credentials, but this barrier is often overcome through credential theft, social engineering, or other initial access techniques. The affected versions span multiple major releases, indicating a prolonged period during which organizations were exposed to this vulnerability, making it a significant concern for enterprise security teams. Organizations that have not patched their systems remain vulnerable to attacks that could result in data breaches, regulatory compliance violations, and operational disruptions.
Mitigation strategies for CVE-2020-7032 should focus on immediate patching of affected systems, with organizations prioritizing the application of vendor-provided security updates. The most effective immediate solution involves updating to versions of avaya weblm that have addressed this vulnerability, as these patches typically include proper xml entity validation and disable the problematic external entity processing capabilities. Network segmentation and access control measures should be implemented to limit the scope of potential exploitation, particularly restricting access to the weblm administrative interface to trusted networks and users. Additional protective measures include implementing xml parser configuration changes that disable external entity resolution and dtd processing, which aligns with security best practices outlined in owasp xml external entity prevention cheat sheet. Organizations should also consider implementing web application firewalls that can detect and block malicious xml requests containing suspicious entity references. Regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of the vulnerable software, while security monitoring should be enhanced to detect unusual xml processing activities or unauthorized file access attempts. The vulnerability also highlights the importance of proper input validation and secure coding practices, particularly when processing xml data, and organizations should review their xml parsing implementations to ensure compliance with established security standards and industry best practices.