In SurrealDB instances with the scripting capability enabled (--allow-scripting), users with the ability to run arbitrary queries can trigger a server crash due to a memory-safety bug in the underlying JS engine. The SurrealDB instance terminates instantly, requiring a manual restart.
The query consists of using built-in string functions to construct a large string and passing it to the JavaScript runtime for compilation. The exact string size required to trigger the crash varies between SurrealDB versions.
Whilst exploiting the vulnerability requires users to be able to run arbitrary queries, if guest access (--allow-guests), is enabled, then guests can perform this attack.
Any user able to execute queries on a SurrealDB instance with scripting enabled (--allow-scripting) can cause complete denial of service. The server process terminates immediately without graceful shutdown.
The underlying cause of the vulnerability is a null pointer dereference in the QuickJS-NG v0.8 JavaScript engine, this vulnerability cannot be exploited to execute arbitrary code, or compromise the integrity or confidentiality of data.
Versions prior to SurrealDB v2.6.1 and v3.0.0-beta.3 are vulnerable.
The patches for SurrealDB v2.6.1 and v3.0.0-beta.3 update the rquickjs dependency from v0.9.0 to v0.11.0, which in turn uses an updated version of QuickJS-NG.
Deny execution of embedded scripting functions through the configuration of capabilities by starting SurrealDB with the --deny-scripting flag or the equivalent environment variable SURREAL_CAPS_DENY_SCRIPT=true. This has a usability implication, although scripting functions are disabled by default.
Administrators can also use --deny-arbitrary-query to deny arbitrary querying by either guest, record or system users, or a combination of those, with impacts to functionality for those users.
SurrealDB Documentation - Capabilities SurrealDB Documentation - Guest Access SurrealQL Documentation - Scripting Functions quickjs-ng v0.9 Release Notes https://github.com/surrealdb/surrealdb/pull/6833 https://github.com/surrealdb/surrealdb/pull/6774
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.