📅 Disclosure & Patch Status

• Publicly disclosed on July 8, 2025, as part of Microsoft’s July Patch Tuesday.
• Affects SQL Server 2016, 2017, 2019, and 2022 (various x64 builds prior to the July 8, 2025 cumulative updates).
• Fixed in the July 2025 cumulative security updates, such as KB5058713 for SQL Server 2019 and KB5058721 for SQL Server 2022.

🔍 Vulnerability Description
This vulnerability is categorized as Improper Input Validation (CWE‑20). A flaw in how SQL Server handles crafted network input can allow an attacker to retrieve uninitialized memory, which may contain sensitive information such as connection strings, login credentials, or internal schema data.

🎯 Attack Characteristics

• Access Vector: Remote (network)
• Authentication Required: No
• User Interaction Required: No
• Privileges Required: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: None
• Availability Impact: None
• CVSS v3.1 Score: 7.5 (High)
• Exploitability: Less likely (per Microsoft), but proof-of-concept code is already public

⚠️ Risk & Impact
An unauthenticated remote attacker can exploit this vulnerability to extract sensitive data from memory. While the attack is passive (it doesn't directly alter or destroy data), the leakage of credentials or internal configurations can lead to significant compromise, including further lateral movement within the environment or targeting of dependent applications.

✅ Mitigation & Remediation

1. Apply the July 2025 security updates:
2. SQL Server 2022: KB5058721
3. SQL Server 2019: KB5058713
4. SQL Server 2017: KB5058714
5. SQL Server 2016: Apply the latest GDR or CU from July 2025
6. Update OLE DB drivers to version 18 or 19
7. Restrict SQL Server network exposure to only trusted hosts and segments
8. Monitor logs for unusual login attempts or memory-related errors (e.g., error 701, 17803)
9. Rotate any credentials or connection strings potentially exposed
10. Enforce network segmentation and least-privilege access to minimize impact

📝 Summary
CVE‑2025‑49719 is a high-severity vulnerability in Microsoft SQL Server that allows unauthenticated attackers to extract memory content remotely. While classified as “less likely” to be exploited, the availability of public proof-of-concept code means organizations should prioritize patching, restrict access to database servers, and monitor for suspicious activity.