Executive brief
Microsoft SQL Server contains an integer underflow vulnerability that allows an authorized user to read sensitive information stored locally on the system. While exploitation requires valid credentials, the flaw could enable insider threats or compromised accounts to access data beyond their intended permission level, potentially exposing confidential business information or customer records.
Technical details
An integer underflow (wrap-around) vulnerability exists in Microsoft SQL Server that can be triggered by an authenticated attacker with local access. The vulnerability occurs when integer arithmetic operations underflow, causing wraparound behavior that bypasses security checks or accesses unintended memory regions. Exploitation requires valid credentials and local system access; the attacker can then craft specific queries or commands to trigger the underflow and read sensitive information from the SQL Server process memory or protected data structures. The vulnerability is classified as medium severity with a CVSS score of 5.5, reflecting the authentication requirement while acknowledging the potential for information disclosure.
Affected products
- Microsoft SQL Server
Timeline
- 2026-09-08: disclosed