CVE-2026-46871: MySQL Shell Unauthorized Data Access via Access Control Bypass

Technical summary

This vulnerability in MySQL Shell is rooted in improper access control (CWE-284). The flaw permits a low-privileged authenticated user to bypass confidentiality protections and gain unauthorized read access to data that should be restricted. The attack vector is network-based, requires no user interaction, and exploits a configuration or permission logic failure. The CVSS 3.1 score of 6.5 reflects high confidentiality impact with no integrity or availability compromise. The relatively low barrier to exploitation (low attack complexity, low privilege requirement) and direct network accessibility make this a moderate-severity concern for organizations using MySQL Shell.

Business impact

Organizations relying on MySQL Shell for database administration face potential exposure of sensitive credentials, connection strings, query history, or other confidential data accessible through the shell environment. Since MySQL Shell is often used by developers and DBAs with legitimate database access, a compromised account could expose information tied to critical database operations. The impact is primarily informational—attackers cannot delete or modify data—but exposure of authentication material or sensitive queries could lead to secondary exploitation or compliance violations depending on data classification.

Affected systems

MySQL Shell version 2026.2.0+9.6.1 is confirmed affected. This includes the MySQL Shell VS Code extension bundled with or used alongside this version. Organizations should verify the exact version running in their environment, as the affected version references a specific 9.6.1 revision level. Environments where non-privileged database users access MySQL Shell, or where shared development machines run the tool, face higher risk.

Exploitability

Exploitation requires an attacker to possess valid MySQL Shell credentials or database account access—this is not an unauthenticated attack. Once authenticated, the attack is trivial to execute over the network with no additional user interaction or complex techniques required. This limits the threat to insiders, compromised employee accounts, or scenarios where database access has been previously obtained. The ease of exploitation once network access and credentials exist makes rapid patching important in multi-tenant or shared-access environments.

Remediation

Apply the latest MySQL Shell patch released by Oracle. Verify the patched version through Oracle's official MySQL Shell release notes and advisory documentation. As an interim control, restrict network access to MySQL Shell instances, limit database account privileges to the minimum required for legitimate workflows, and monitor for unusual data access patterns from authenticated sessions. Consider segmenting development and production MySQL Shell usage onto separate networks or workstations.

Patch guidance

Consult Oracle's MySQL Shell product release notes and security advisories at dev.mysql.com for patch availability and version numbers. Patches typically address the access control logic in the shell component. Test the patched version in a non-production environment before deploying to ensure compatibility with existing automation, IDE integrations, or scripts. Version 2026.2.0+9.6.1 should be updated to the next available maintenance release that includes the fix.

Detection guidance

Monitor MySQL Shell activity logs for unusual data access by low-privileged accounts, particularly queries or operations on sensitive tables or schemas. In network-based detection, look for authenticated connections to MySQL Shell that trigger data retrieval operations outside normal patterns. Review IDE extension logs if using the VS Code integration. Correlation between successful authentication and subsequent high-volume data exports or reads may indicate exploitation. Enable audit logging on database accounts used with MySQL Shell if available.

Why prioritize this

This vulnerability merits near-term patching due to its ease of exploitation, network accessibility, and direct impact on confidentiality of database-related secrets. While it requires valid credentials, the barrier to obtaining those credentials in development and internal environments is often lower than in production systems. Organizations with shared MySQL Shell instances or relaxed credential management should prioritize this higher. CVSS 6.5 (MEDIUM) severity combined with accessibility and ease of exploit justifies prompt remediation.

Risk score, explained

The CVSS 3.1 Base Score of 6.5 (MEDIUM) reflects high confidentiality impact (C:H) balanced against no integrity or availability loss. The 'low' attack complexity and 'low' privilege requirement lower the barrier to exploitation compared to critical vulnerabilities, but network accessibility (AV:N) and the lack of user interaction needed (UI:N) keep the score elevated. This is not a critical flaw because impact is limited to confidentiality and the attacker must already be authenticated; however, it represents a real and easily exploitable exposure path.

Frequently asked questions