As our SOC analysts have been monitoring the latest Patch Tuesday updates, we noticed that while several critical vulnerabilities were addressed, some flaws may still be exploited by attackers to move laterally within your organization. In this post, we'll break down the Microsoft Copilot tampering vulnerability and the SSO plugin for Jira & Confluence elevation of privilege flaw, and explain how an attacker can chain these two to gain access to your Microsoft 365 tenant.
What Is the Microsoft Copilot Tampering Vulnerability?
As its name suggests, the Microsoft Copilot tampering vulnerability allows an attacker to tamper with the Microsoft Copilot AI-powered tool, potentially leading to unauthorized access to sensitive data. The vulnerability is tracked as CVE-2026-11499 and has been rated as critical by Microsoft.
How Does the SSO Plugin Privilege Escalation Flaw Work?
The SSO plugin for Jira & Confluence elevation of privilege flaw allows an attacker to escalate their privileges within the Atlassian workspace, potentially gaining access to sensitive data and systems. The flaw is tracked as CVE-2023-54352 and has been rated as critical by Atlassian.
How Can an Attacker Chain These Two Vulnerabilities?
An attacker can chain the Microsoft Copilot tampering vulnerability and the SSO plugin privilege escalation flaw to move laterally from a developer's Atlassian workspace into your Microsoft 365 tenant. Here's a step-by-step example:
- The attacker gains access to a developer's Atlassian workspace, potentially through phishing or other social engineering tactics.
- The attacker exploits the SSO plugin privilege escalation flaw to gain elevated privileges within the Atlassian workspace.
- The attacker uses their elevated privileges to access the Microsoft Copilot tool, potentially tampering with the AI-powered functionality.
- The attacker uses the tampered Microsoft Copilot tool to gain access to sensitive data and systems within the Microsoft 365 tenant.
What Compensating Controls Can You Implement?
While patches are being deployed, there are several compensating controls you can implement to reduce the risk of lateral movement attacks:
- Implement multi-factor authentication (MFA) to prevent unauthorized access to sensitive data and systems.
- Limit privileges to the minimum required for each user and system.
- Monitor for suspicious activity, such as unusual login attempts or access to sensitive data.
- Implement a web application firewall (WAF) to detect and prevent common web attacks.
How Can Continuous Monitoring Help?
Continuous monitoring can help detect and prevent lateral movement attacks by monitoring for suspicious activity and behavioral indicators. Our SOC analysts use a combination of threat intelligence, anomaly detection, and machine learning to identify potential threats and alert our customers to take action.
What Is the Severity of These Vulnerabilities?
The Microsoft Copilot tampering vulnerability and the SSO plugin privilege escalation flaw have both been rated as critical by their respective vendors. The severity of these vulnerabilities is high, and organizations should prioritize patching and implementing compensating controls as soon as possible.
What Are the Relevant Frameworks and Regulations?
Several frameworks and regulations are relevant to the Microsoft Copilot tampering vulnerability and the SSO plugin privilege escalation flaw, including:
- NIST Cybersecurity Framework
- ISO 27001
- SOC 2
- CIS Controls
- GDPR
- HIPAA
Final Thoughts
The June 2026 Patch Tuesday addressed several critical vulnerabilities, but some flaws may still be exploited by attackers. By understanding the Microsoft Copilot tampering vulnerability and the SSO plugin privilege escalation flaw, and implementing compensating controls and continuous monitoring, you can reduce the risk of lateral movement attacks and protect your organization's sensitive data and systems. For more information on how to protect your organization, check out our Penetration Testing and Vulnerability Assessment services.