SurrealDB before 2.2.2 CPU Exhaustion via nested FOR loops

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 2.0.5, 2.1.x before 2.1.5, and 2.2.x before 2.2.2 allows authenticated users with OWNER or EDITOR permissions (at the root, namespace, or database level) to define custom database functions via DEFINE FUNCTION using nested FOR loops. Although a single loop's iteration count is constrained, nesting multiple loops (e.g., each with 1,000,000 iterations) is not, so an attacker can execute a function that consumes all server CPU time. Configured timeouts do not stop the execution, rendering the server unresponsive to other queries and connections until it is manually restarted.

Source published

18 Jul 2026 13:10:15 UTC

Source modified

29 Oct 2026 21:15:23 UTC

Observed here

29 Oct 2026 22:48:55 UTC

Source terms

CVE Program Terms of Use

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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: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SurrealDB before 2.0.5, 2.1.x before 2.1.5, and 2.2.x before 2.2.2 allows authenticated users with OWNER or EDITOR permissions (at the root, namespace, or database level) to define custom database functions via DEFINE FUNCTION using nested FOR loops. Although a single loop's iteration count is constrained, nesting multiple loops (e.g., each with 1,000,000 iterations) is not, so an attacker can execute a function that consumes all server CPU time. Configured timeouts do not stop the execution, rendering the server unresponsive to other queries and connections until it is manually restarted.

Source published

Jul 18, 2026, 1:10:15 PM (timezone not stated)

Source modified

Oct 29, 2026, 9:15:23 PM (timezone not stated)

Observed here

5 Nov 2026 03:02:36 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 · 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SurrealDB before 2.0.5, 2.1.x before 2.1.5, and 2.2.x before 2.2.2 allows authenticated users with OWNER or EDITOR permissions (at the root, namespace, or database level) to define custom database functions via DEFINE FUNCTION using nested FOR loops. Although a single loop's iteration count is constrained, nesting multiple loops (e.g., each with 1,000,000 iterations) is not, so an attacker can execute a function that consumes all server CPU time. Configured timeouts do not stop the execution, rendering the server unresponsive to other queries and connections until it is manually restarted.

Source published

18 Jul 2026 14:17:11 UTC

Source modified

29 Oct 2026 21:17:06 UTC

Observed here

31 Oct 2026 06:45:43 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 · 7.1 CVSS:4.0/AV:N/AC:L/AT:N/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

SurrealDB allows authenticated users with `OWNER` or `EDITOR` permissions at the root, database or namespace levels to define their own database functions using the `DEFINE FUNCTION` statement A custom database function comprises a name together with a function body. In the function body, the user programs the functionality of the function in terms of SurrealQL. The language includes a `FOR` keyword, used to implement for-loops. Whilst the parser and interpreter constrain the number of iterations for a single for-loop, nesting several for-loops with a large number of iterations is possible. Thus, an attacker could define a function that comprises several nested for-loops with an iteration count of 1.000.000 each. Executing the function will consume all the CPU time of the server, timeouts configured will not break the CPU consumption, and the function execution monopolizes all CPU time of the SurrealDB server, effectively preventing the server from executing functions, queries, commands of other users, or allowing further connections being established to the server. Terminating the stuck server requires manual intervention which forces a quit on the server process, as the server application is not responsive any longer. This issue was discovered and patched during an code audit and penetration test of SurrealDB by cure53, the severity defined within cure53's preliminary finding is high, matched by our CVSS v4 assessment. ### Impact Denial of Service vulnerability resulting in a stuck SurrealDB server requiring manual restart. ### Patches A patch has been introduced that adds a check in the `ForEachStatement` that checks if the context has been cancelled or timed out for every iteration. - Versions 2.0.5, 2.1.5, 2.2.2, and later are not affected by this issue. ### Workarounds For SurrealDB users that are unable to upgrade, consider setting the `--allow-functions` and/or `--deny-functions` options or corresponding `SURREAL_CAPS_ALLOW_FUNC` and/or `SURREAL_CAPS_DENY_FUNC` environment variables, documented within [capabilities](https://surrealdb.com/docs/surrealdb/security/capabilities#functions), to either block all custom functions, or only allow trusted functions to execute. ### References [SurrealQL Documentation - DEFINE FUNCTION Statement](https://surrealdb.com/docs/surrealql/statements/define/function) [SurrealQL Documentation - FOR Statement](https://surrealdb.com/docs/surrealql/statements/for) [SurrealDB Documentation - Capabilities](https://surrealdb.com/docs/surrealdb/security/capabilities#functions) [SurrealDB Documentation - Environment variables](https://surrealdb.com/docs/surrealdb/cli/env#command-environment-variables) [#5597](https://github.com/surrealdb/surrealdb/pull/5597)

Source published

11 Apr 2025 14:09:14 UTC

Source modified

19 Jul 2026 03:56:48 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:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Publisher rating · HIGH