CVE-2025-6514: MCP Servers — AI Credential Exposure Risk (August 2026)

CVE-2025-6514 — MCP Servers

CVE-2025-6514 is a high-severity vulnerability affecting MCP servers that enable AI agents to access enterprise tools and data. The flaw allows attackers to extract plaintext credentials, exploit over-permissioned accounts, and leverage prompt injection to escalate privileges or exfiltrate sensitive data. No official CVSS score is published, but the risk profile is critical due to the potential for broad enterprise compromise.

Attack Vector

Attackers target MCP server deployments where credentials and long-lived secrets are stored in plaintext within configuration files or environment variables. By gaining access to these files—via local compromise, misconfigured permissions, or supply chain weaknesses—attackers can harvest credentials for further lateral movement. Additionally, prompt injection attacks against AI agents connected to MCP servers can trick agents into revealing secrets or executing unauthorized actions under the guise of legitimate automation. Over-permissioned MCP instances amplify the impact, allowing attackers to act with broad enterprise privileges.

Who Is at Risk

Any organization deploying MCP servers to facilitate AI agent access to enterprise systems is at risk, especially those with default or insecure configurations. Both on-premises and cloud-based MCP deployments are vulnerable if secrets are not secured and agent permissions are overly broad. No specific organizations are named, but the exposure is global and cross-industry.

Patch & Mitigate

• Patch: Apply vendor-issued security updates for MCP servers as soon as available. If no patch, restrict access to configuration files and rotate all stored credentials immediately.
• Workaround: Store credentials in secure vaults, not plaintext. Limit MCP server and agent permissions to the minimum required.
• Detect: Monitor for unusual access to configuration files, unexpected AI agent actions, and anomalous privilege escalations. Audit logs for prompt injection attempts or unauthorized system changes.

MITRE ATT&CK

• TA0001 — Initial Access: Attackers exploit exposed credentials to gain entry.
• TA0005 — Defense Evasion: Prompt injection and over-permissioning enable stealthy lateral movement.
• TA0006 — Credential Access: Direct harvesting of plaintext secrets from configuration files.

Source: https://thehackernews.com/2026/08/how-mcp-servers-can-expose-enterprise.html