SQL Server Deserialization of Untrusted Data Remote Code Execution
Severe, but no confirmed exploitation yet. Schedule remediation in your next patch cycle and apply mitigations if you're exposed.
An attacker with a basic user account, remotely over the network, with no user interaction, can fully compromise the system — steal data, tamper with it and take it offline.
Deserialization of untrusted data in SQL Server allows an authorized attacker to execute code over a network.
Inferred from the weakness type (CWE) and how the flaw is reached — the techniques an attacker would chain to exploit this. Real-world corroboration appears here as threat intel is folded in.
Generated by Wavense from the CVE record — an immediate mitigation and the permanent fix.
Implement strict least privilege principles for all SQL Server accounts, ensuring they only have necessary permissions. Restrict network access to SQL Server instances via firewalls and network segmentation, limiting connections only from trusted hosts and services. Enhance monitoring for unusual process execution originating from the SQL Server service account and suspicious outbound connections.
The permanent resolution requires applying the official security patch released by Microsoft for SQL Server to address CVE-2026-77484. Administrators should identify all affected SQL Server versions and instances within their environment. Plan for a controlled upgrade process to the patched version as soon as it becomes available to fully remediate the vulnerability.
An authorized attacker can leverage this vulnerability to execute arbitrary code remotely on the SQL Server instance. This grants them full control over the database server, enabling data exfiltration, modification, or even deploying further malware within the network. The business consequences include severe data breaches, service outages, and significant reputational and financial damage.
Other CVEs affecting sql server 2019
Heap-based buffer overflow in SQL Server allows an unauthorized attacker to execute code over a network.
Heap-based buffer overflow in SQL Server allows an unauthorized attacker to execute code over a network.
Deserialization of untrusted data in SQL Server allows an unauthorized attacker to execute code over a network.
Deserialization of untrusted data in SQL Server allows an unauthorized attacker to execute code over a network.
Out-of-bounds read in SQL Server allows an unauthorized attacker to execute code over a network.
Untrusted pointer dereference in SQL Server allows an unauthorized attacker to execute code over a network.