The KILL statement is used to terminate LIVE SELECT subscriptions that capture real-time changes to data within a table. The KILL statement implementation in core/src/expr/statements/kill.rs verifies that the requesting user has database-level access, but does not verify that the requesting user is the owner of the live query being terminated.
After passing the valid_for_db() check, the KILL statement resolves the live query UUID, looks up the corresponding live query entry, and immediately deletes it without comparing the requesting user's identity against the live query owner. This allows any authenticated user with database-level access to terminate any live query in that database, regardless of who created it.
The affected user's real-time subscription silently stops receiving updates with no notification that the live query was terminated. The same attack works across privilege levels: a low-privilege record-scoped user can terminate a root user's monitoring live queries.
This issue was discovered and patched during a code audit and penetration test of SurrealDB by cure53, the severity defined within cure53's preliminary finding is Medium, matched by our CVSS v3.1 assessment.
An authenticated user with database-level access can terminate any other user's live query subscriptions within the same database by issuing a KILL statement with the target live query's UUID. This impacts availability by silently disrupting real-time data subscriptions and breaks multi-tenant isolation guarantees.
The attack requires knowledge of the target live query UUID. Live query UUIDs are randomly generated, but may be exposed through application logs, shared monitoring dashboards, or other information disclosure vectors.
An ownership verification check has been introduced in the KILL statement implementation that compares the requesting user's authentication context against the owner of the live query before allowing deletion.
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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.