External risk intelligence

Zimbra Collaboration Suite Server-Side Request Forgery Vulnerability

CVE advisoryKnown Exploit

CVE-2020-7796

A vulnerability in Zimbra Collaboration Suite, when the WebEx zimlet is installed and zimlet JSP is enabled, allows for server-side request forgery. This can lead to unauthorized access to internal systems and data, posing a significant business risk.

5Halo Surface Signal

Server-Side Request Forgery

Synacor Zimbra Collaboration Suite

before 8.8.158.8.15

External exposure likelihood

Halo Surface Signal score for CVE-2020-7796

Zimbra Collaboration Suite is an enterprise email and collaboration platform that is typically deployed as a public-facing service, including web-based user portals and administrative interfaces, making it inherently designed for network exposure in normal production environments.

Horizon Alert

Summary of the vulnerability and why it matters

Zimbra Collaboration Suite is vulnerable when the WebEx zimlet is installed and zimlet JSP is enabled. This flaw allows unauthorized access to internal systems by enabling a server-side request forgery. The impact can include unauthorized data access, modification, or denial of service.

Vulnerable component: Zimbra Collaboration Suite with WebEx zimlet
Core weakness: Server-side request forgery
Main business impact: Unauthorized system access and data exposure

Attack Path

How an attacker could exploit the issue

The Zimbra Collaboration Suite is exposed to the network when the WebEx zimlet is installed and the zimlet JSP is enabled. An unauthenticated attacker can exploit this by sending a specially crafted request. This action results in the attacker gaining control over the affected system, potentially leading to unauthorized access, data exfiltration, or system disruption.

Network exposure required.
Unauthenticated attacker access.
Trigger action for control.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability impacts organizations using Zimbra Collaboration Suite with the WebEx zimlet installed and the zimlet JSP enabled. Attackers can exploit this to trick the server into making requests on their behalf, potentially accessing internal resources or sensitive data. The risk is high due to the potential for significant data compromise and system disruption, making it an urgent concern for affected organizations.

Likely attacker skill level: Low
Required access or conditions: Network access, WebEx zimlet, zimlet JSP enabled
Business risk or urgency: High

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

A critical vulnerability exists in Zimbra Collaboration Suite when the WebEx zimlet is installed and zimlet JSP is enabled. This vulnerability could allow attackers to perform server-side requests, potentially leading to unauthorized access or manipulation of data. The risk is amplified as the affected product is often exposed to the network. Organizations must prioritize addressing this issue to protect their systems and sensitive information.

Identify exposed Zimbra assets.
Reduce exposure or isolate affected systems.
Apply vendor fix and validate.
Monitor for related activity.

Frequently asked questions

What is the primary weakness in Zimbra Collaboration Suite that leads to security risks?

The primary weakness is Server-Side Request Forgery (SSRF), identified as CWE-918. This occurs in Zimbra Collaboration Suite versions before 8.8.15 Patch 7 when the WebEx zimlet is installed and its JSP component is enabled. SSRF vulnerabilities allow an attacker to induce the server-side application to make HTTP requests to an arbitrary domain of the attacker's choosing, potentially exposing internal systems and data.

How does the Server-Side Request Forgery (SSRF) vulnerability manifest in Zimbra Collaboration Suite?

The SSRF vulnerability in Zimbra Collaboration Suite is triggered when the WebEx zimlet is installed and the zimlet JSP is enabled. An unauthenticated attacker can exploit this by sending a specially crafted request. This causes the server to make unintended requests on behalf of the attacker, leading to unauthorized access to internal systems, data exfiltration, or denial of service.

What is the threat posed by CVE-2020-7796 to organizations using Zimbra Collaboration Suite?

CVE-2020-7796, a Server-Side Request Forgery vulnerability in Zimbra Collaboration Suite (ZCS), poses a significant threat. When the WebEx zimlet and zimlet JSP are enabled, an attacker can exploit this to trick the server into making requests to internal or external resources. This can result in unauthorized access to sensitive data, compromise of internal systems, and potential disruption of services, representing a high business risk and urgency.

What is the relevance of the Halo Surface Signal assessment for CVE-2020-7796?

The Halo Surface Signal assesses CVE-2020-7796 as 'Very likely' to be exploited due to the nature of Zimbra Collaboration Suite. This platform is typically deployed as a public-facing service with web-based portals, making it inherently exposed to the network in normal operating environments. This network exposure significantly increases the attack surface and the likelihood of exploitation.

What practical steps should be taken to respond to the Zimbra Collaboration Suite vulnerability?

To respond practically, organizations must first identify all exposed Zimbra assets. It is crucial to reduce the network exposure of affected systems or isolate them if possible. Applying the vendor-provided fix, specifically Zimbra Collaboration Suite 8.8.15 Patch 7 or later, is essential. After applying the patch, validate the remediation and continuously monitor for any related suspicious activity to ensure the threat is neutralized.

References

Written by Nicholas Merritt

External-surface CVE analysis and Halo Surface Signal prioritization for Halo Threat Intelligence.