CVE-2021-20788 : Security Advisory and Response

Server-side request forgery (SSRF) vulnerability in GroupSession allows a remote attacker to conduct a port scan and obtain internal information. The affected versions include GroupSession Free edition from ver2.2.0 to ver5.1.0, GroupSession byCloud from ver3.0.3 to ver5.1.0, and GroupSession ZION from ver3.0.3 to ver5.1.0.

Understanding CVE-2021-20788

This CVE entry describes a Server-Side Request Forgery (SSRF) vulnerability impacting GroupSession software.

What is CVE-2021-20788?

The vulnerability in GroupSession enables a remote authenticated attacker to execute a port scan and extract data from the internal Web server.

The Impact of CVE-2021-20788

With this SSRF flaw, threat actors can gather sensitive information, potentially leading to unauthorized access and data breaches.

Technical Details of CVE-2021-20788

The technical aspects of this CVE include:

Vulnerability Description

The SSRF vulnerability in GroupSession permits authenticated attackers to probe ports and retrieve data from internal servers.

Affected Systems and Versions

The impacted versions of GroupSession are Free edition from ver2.2.0 to ver5.1.0, byCloud from ver3.0.3 to ver5.1.0, and ZION from ver3.0.3 to ver5.1.0.

Exploitation Mechanism

Attackers with authenticated access can exploit this flaw to scan ports and extract sensitive information.

Mitigation and Prevention

To address CVE-2021-20788, consider the following:

Immediate Steps to Take

Ensure immediate patching or update to a secure version.
Conduct security audits and restrict network access.

Long-Term Security Practices

Regularly monitor and update software components.
Implement access controls and security protocols.

Patching and Updates

Stay informed about security advisories and apply patches promptly to prevent exploitation of vulnerabilities.