SurrealDB before v2.6.1 Denial of Service via scripting

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

SurrealDB before v2.6.1 (and before v3.0.0-beta.3) contains a denial of service vulnerability in its embedded JavaScript scripting engine, which is enabled via the --allow-scripting capability (disabled by default). Any user able to execute arbitrary queries — including unauthenticated guests when --allow-guests is enabled — can use built-in string functions to construct a large string and pass it to the JavaScript runtime for compilation, triggering a null pointer dereference in the underlying QuickJS-NG engine. This causes the server process to terminate immediately without graceful shutdown, requiring a manual restart. The issue was fixed by updating the rquickjs dependency from v0.9.0 to v0.11.0.

Source published

20 Jul 2026 12:04:51 UTC

Source modified

8 Oct 2026 15:23:51 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SurrealDB before v2.6.1 (and before v3.0.0-beta.3) contains a denial of service vulnerability in its embedded JavaScript scripting engine, which is enabled via the --allow-scripting capability (disabled by default). Any user able to execute arbitrary queries — including unauthenticated guests when --allow-guests is enabled — can use built-in string functions to construct a large string and pass it to the JavaScript runtime for compilation, triggering a null pointer dereference in the underlying QuickJS-NG engine. This causes the server process to terminate immediately without graceful shutdown, requiring a manual restart. The issue was fixed by updating the rquickjs dependency from v0.9.0 to v0.11.0.

Source published

Jul 20, 2026, 12:04:51 PM (timezone not stated)

Source modified

Oct 8, 2026, 3:23:51 PM (timezone not stated)

Observed here

9 Nov 2026 14:13:50 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SurrealDB before v2.6.1 (and before v3.0.0-beta.3) contains a denial of service vulnerability in its embedded JavaScript scripting engine, which is enabled via the --allow-scripting capability (disabled by default). Any user able to execute arbitrary queries — including unauthenticated guests when --allow-guests is enabled — can use built-in string functions to construct a large string and pass it to the JavaScript runtime for compilation, triggering a null pointer dereference in the underlying QuickJS-NG engine. This causes the server process to terminate immediately without graceful shutdown, requiring a manual restart. The issue was fixed by updating the rquickjs dependency from v0.9.0 to v0.11.0.

Source published

20 Jul 2026 12:19:46 UTC

Source modified

22 Jul 2026 19:41:01 UTC

Observed here

25 Oct 2026 15:18:45 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS 3.1 · [email protected] · Primary · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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. ### Impact 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. ### Patches 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`. ### Workarounds Deny execution of embedded scripting functions through the configuration of [capabilities](https://surrealdb.com/docs/surrealdb/security/capabilities#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. ### Links ### [SurrealDB Documentation - Capabilities](https://surrealdb.com/docs/surrealdb/security/capabilities) [SurrealDB Documentation - Guest Access](https://surrealdb.com/docs/surrealdb/security/capabilities#guest-access) [SurrealQL Documentation - Scripting Functions](https://surrealdb.com/docs/surrealql/functions/script) [quickjs-ng v0.9 Release Notes](https://github.com/quickjs-ng/quickjs/releases/tag/v0.9.0) https://github.com/surrealdb/surrealdb/pull/6833 https://github.com/surrealdb/surrealdb/pull/6774

Source published

12 Feb 2026 22:11:48 UTC

Source modified

21 Jul 2026 03:56:46 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Publisher rating · MODERATE