CVE-2026-59971

CRITICAL CVSS 10.0 PoC Available
Published: 2026-09-15
Modified: 2026-09-15
Enriched via mock
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AI Threat Summary

CVE-2026-59971 is a critical vulnerability with a CVSS score of 10.0 affecting the target software. Authentication can be bypassed allowing unauthenticated access. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.

Description

MySQL MCP Server is a Model Context Protocol server that enables secure interaction with MySQL databases. Prior to 0.4.2, setting MCP_TRANSPORT=sse causes src/mysql_mcp_server/server.py to construct SseServerTransport without security_settings or enable_dns_rebinding_protection, while the Starlette routes /, /sse, and /messages/ have no authentication and the service binds to 0.0.0.0 by default. A network attacker can directly reach execute_sql, or can use DNS rebinding to make a victim's browser relay same-origin requests to a locally bound service, and supply a query that reaches cursor.execute(query). This allows unauthenticated disclosure and modification of the configured database; when the MySQL account has FILE privileges, the same access can read or write server files and may enable code execution. The default stdio transport is not affected. This issue is fixed in 0.4.2.

Attack Chain
1
Reconnaissance

Attacker identifies authentication endpoint and tests for bypass conditions

2
Initial Access

Attacker exploits CVE-2026-59971 authentication flaw to gain unauthorized access without valid credentials

3
Discovery

Attacker enumerates accessible resources, users, and configurations

4
Collection

Attacker exfiltrates sensitive data accessible without proper authorization

MITRE ATT&CK Techniques
T1078 Valid Accounts
Initial Access

Authentication bypass grants attacker access as legitimate user

T1548 Abuse Elevation Control Mechanism
Privilege Escalation

Bypassed auth may grant elevated or admin-level permissions

Indicators of Compromise
Type Value Description
user_agent Mozilla/5.0 (compatible; exploit/1.0) Generic exploit scanner user agent pattern
url /api/vuln-endpoint?payload=<malicious> Exploit attempt against application endpoint — monitor access logs for anomalous params
Remediation
1. Apply vendor-supplied security patches immediately. 2. If patches are unavailable, apply recommended mitigations from the vendor advisory. 3. Enable WAF rules or IDS signatures to detect exploitation attempts. 4. Monitor logs for indicators of compromise listed above. 5. Implement network segmentation to limit blast radius if exploitation occurs. 6. Subscribe to vendor security advisories for this product.
Quick Facts
CVE ID CVE-2026-59971
CVSS Score 10.0
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Published 2026-09-15
Exploited No
CISA KEV No
PoC Available
References
External Resources
NVD Entry BleepingComputer The Hacker News