CVE-2025-24986: Azure Promptflow Core RCE Vulnerability

CVE-2025-24986 Overview

CVE-2025-24986 is an improper isolation or compartmentalization vulnerability in Microsoft Azure PromptFlow that allows an unauthorized attacker to execute code over a network. This vulnerability affects the Azure PromptFlow Core and Azure PromptFlow Tools components, which are critical for building and deploying AI-powered applications in the Microsoft Azure ecosystem.

The flaw stems from inadequate isolation mechanisms within the PromptFlow execution environment, potentially allowing attackers to escape sandboxed contexts and execute arbitrary code on the underlying infrastructure.

Critical Impact

Unauthorized network-based attackers can execute code on Azure PromptFlow instances without authentication, potentially compromising AI/ML pipelines and sensitive data processing workflows.

Affected Products

• Microsoft Azure PromptFlow Core
• Microsoft Azure PromptFlow Tools

Discovery Timeline

• March 11, 2025 - CVE-2025-24986 published to NVD
• July 10, 2025 - Last updated in NVD database

Technical Details for CVE-2025-24986

Vulnerability Analysis

This vulnerability is classified under CWE-653 (Improper Isolation or Compartmentalization), indicating that the affected software fails to properly isolate or compartmentalize functionality, data, or execution environments. In the context of Azure PromptFlow, this means that the boundaries between different execution contexts or user sessions may not be adequately enforced.

Azure PromptFlow is a development tool designed to streamline the creation of AI applications by connecting large language models (LLMs), prompts, and Python tools. The improper isolation issue could allow an attacker to break out of the intended execution sandbox and gain access to resources or capabilities that should be restricted.

The network-based attack vector means exploitation can occur remotely without requiring physical access to the target system. The vulnerability can be exploited without any user interaction and without requiring prior authentication, making it particularly dangerous in multi-tenant cloud environments.

Root Cause

The root cause of CVE-2025-24986 lies in insufficient compartmentalization controls within the Azure PromptFlow execution framework. The software fails to adequately isolate execution environments, allowing cross-boundary access between components that should remain separated. This architectural weakness enables attackers to bypass intended security boundaries and execute unauthorized operations.

Attack Vector

The attack vector is network-based, allowing remote exploitation without user interaction or authentication requirements. An attacker could potentially:

1. Craft malicious requests targeting the PromptFlow service endpoints
2. Exploit the isolation boundary weakness to escape the sandboxed execution context
3. Execute arbitrary code within the context of the Azure PromptFlow service
4. Potentially access or manipulate data from other tenants or workflows sharing the same infrastructure

The vulnerability mechanism involves exploiting the weak compartmentalization between execution contexts. The attacker can leverage network access to the PromptFlow service to inject or execute code that breaks out of the intended isolation boundaries. For detailed technical information, refer to the Microsoft Security Update for CVE-2025-24986.

Detection Methods for CVE-2025-24986

Indicators of Compromise

• Unexpected or unauthorized code execution within Azure PromptFlow workflows
• Anomalous network connections originating from PromptFlow instances to internal resources
• Unusual process spawning or system calls from PromptFlow execution contexts
• Log entries indicating attempts to access resources outside permitted boundaries

Detection Strategies

• Monitor Azure PromptFlow service logs for suspicious activity patterns or unauthorized execution attempts
• Implement network traffic analysis to detect unusual outbound connections from PromptFlow instances
• Deploy runtime application self-protection (RASP) solutions to detect sandbox escape attempts
• Utilize Azure Security Center alerts for anomalous behavior in AI/ML workloads

Monitoring Recommendations

• Enable comprehensive logging for all Azure PromptFlow Core and Tools components
• Configure Azure Monitor alerts for unusual execution patterns or resource access attempts
• Implement network segmentation monitoring to detect lateral movement attempts
• Review audit logs regularly for signs of unauthorized code execution

How to Mitigate CVE-2025-24986

Immediate Actions Required

• Review and update Azure PromptFlow Core and Azure PromptFlow Tools to the latest patched versions
• Audit existing PromptFlow deployments for signs of compromise
• Implement network access controls to restrict PromptFlow service exposure
• Enable enhanced monitoring and logging for all PromptFlow instances

Patch Information

Microsoft has released security updates to address this vulnerability. Organizations should apply the official patches as documented in the Microsoft Security Update Guide for CVE-2025-24986. Ensure all Azure PromptFlow Core and Azure PromptFlow Tools installations are updated to versions that include the fix.

Workarounds

• Restrict network access to Azure PromptFlow services using Azure Network Security Groups (NSGs) and firewall rules
• Implement additional authentication layers such as Azure AD Conditional Access for accessing PromptFlow endpoints
• Deploy Azure Private Endpoints to limit PromptFlow service exposure to trusted networks only
• Consider temporary isolation of PromptFlow workloads until patches can be applied

# Example: Configure Azure NSG rule to restrict PromptFlow access
az network nsg rule create \
  --resource-group <resource-group-name> \
  --nsg-name <nsg-name> \
  --name RestrictPromptFlowAccess \
  --priority 100 \
  --source-address-prefixes <trusted-ip-ranges> \
  --destination-port-ranges 443 \
  --access Allow \
  --protocol Tcp \
  --direction Inbound