Search for packages
| purl | pkg:npm/qs@1.2.2 |
| Vulnerability | Summary | Fixed by |
|---|---|---|
|
VCID-9ykq-nq81-4fcp
Aliases: CVE-2025-15284 GHSA-6rw7-vpxm-498p |
qs's arrayLimit bypass in its bracket notation allows DoS via memory exhaustion The `arrayLimit` option in qs did not enforce limits for bracket notation (`a[]=1&a[]=2`), only for indexed notation (`a[0]=1`). This is a consistency bug; `arrayLimit` should apply uniformly across all array notations. **Note:** The default `parameterLimit` of 1000 effectively mitigates the DoS scenario originally described. With default options, bracket notation cannot produce arrays larger than `parameterLimit` regardless of `arrayLimit`, because each `a[]=value` consumes one parameter slot. The severity has been reduced accordingly. |
Affected by 1 other vulnerability. |
|
VCID-bcuh-2e2c-53gy
Aliases: CVE-2022-24999 GHSA-hrpp-h998-j3pp |
qs vulnerable to Prototype Pollution qs before 6.10.3 allows attackers to cause a Node process hang because an `__ proto__` key can be used. In many typical web framework use cases, an unauthenticated remote attacker can place the attack payload in the query string of the URL that is used to visit the application, such as `a[__proto__]=b&a[__proto__]&a[length]=100000000`. The fix was backported to qs 6.9.7, 6.8.3, 6.7.3, 6.6.1, 6.5.3, 6.4.1, 6.3.3, and 6.2.4. |
Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. Affected by 2 other vulnerabilities. |
|
VCID-pxq3-b7gn-3yah
Aliases: CVE-2026-2391 GHSA-w7fw-mjwx-w883 |
qs's arrayLimit bypass in comma parsing allows denial of service ### Summary The `arrayLimit` option in qs does not enforce limits for comma-separated values when `comma: true` is enabled, allowing attackers to cause denial-of-service via memory exhaustion. This is a bypass of the array limit enforcement, similar to the bracket notation bypass addressed in GHSA-6rw7-vpxm-498p (CVE-2025-15284). ### Details When the `comma` option is set to `true` (not the default, but configurable in applications), qs allows parsing comma-separated strings as arrays (e.g., `?param=a,b,c` becomes `['a', 'b', 'c']`). However, the limit check for `arrayLimit` (default: 20) and the optional throwOnLimitExceeded occur after the comma-handling logic in `parseArrayValue`, enabling a bypass. This permits creation of arbitrarily large arrays from a single parameter, leading to excessive memory allocation. **Vulnerable code** (lib/parse.js: lines ~40-50): ```js if (val && typeof val === 'string' && options.comma && val.indexOf(',') > -1) { return val.split(','); } if (options.throwOnLimitExceeded && currentArrayLength >= options.arrayLimit) { throw new RangeError('Array limit exceeded. Only ' + options.arrayLimit + ' element' + (options.arrayLimit === 1 ? '' : 's') + ' allowed in an array.'); } return val; ``` The `split(',')` returns the array immediately, skipping the subsequent limit check. Downstream merging via `utils.combine` does not prevent allocation, even if it marks overflows for sparse arrays.This discrepancy allows attackers to send a single parameter with millions of commas (e.g., `?param=,,,,,,,,...`), allocating massive arrays in memory without triggering limits. It bypasses the intent of `arrayLimit`, which is enforced correctly for indexed (`a[0]=`) and bracket (`a[]=`) notations (the latter fixed in v6.14.1 per GHSA-6rw7-vpxm-498p). ### PoC **Test 1 - Basic bypass:** ``` npm install qs ``` ```js const qs = require('qs'); const payload = 'a=' + ','.repeat(25); // 26 elements after split (bypasses arrayLimit: 5) const options = { comma: true, arrayLimit: 5, throwOnLimitExceeded: true }; try { const result = qs.parse(payload, options); console.log(result.a.length); // Outputs: 26 (bypass successful) } catch (e) { console.log('Limit enforced:', e.message); // Not thrown } ``` **Configuration:** - `comma: true` - `arrayLimit: 5` - `throwOnLimitExceeded: true` Expected: Throws "Array limit exceeded" error. Actual: Parses successfully, creating an array of length 26. ### Impact Denial of Service (DoS) via memory exhaustion. ### Suggested Fix Move the `arrayLimit` check before the comma split in `parseArrayValue`, and enforce it on the resulting array length. Use `currentArrayLength` (already calculated upstream) for consistency with bracket notation fixes. **Current code** (lib/parse.js: lines ~40-50): ```js if (val && typeof val === 'string' && options.comma && val.indexOf(',') > -1) { return val.split(','); } if (options.throwOnLimitExceeded && currentArrayLength >= options.arrayLimit) { throw new RangeError('Array limit exceeded. Only ' + options.arrayLimit + ' element' + (options.arrayLimit === 1 ? '' : 's') + ' allowed in an array.'); } return val; ``` **Fixed code:** ```js if (val && typeof val === 'string' && options.comma && val.indexOf(',') > -1) { const splitArray = val.split(','); if (splitArray.length > options.arrayLimit - currentArrayLength) { // Check against remaining limit if (options.throwOnLimitExceeded) { throw new RangeError('Array limit exceeded. Only ' + options.arrayLimit + ' element' + (options.arrayLimit === 1 ? '' : 's') + ' allowed in an array.'); } else { // Optionally convert to object or truncate, per README return splitArray.slice(0, options.arrayLimit - currentArrayLength); } } return splitArray; } if (options.throwOnLimitExceeded && currentArrayLength >= options.arrayLimit) { throw new RangeError('Array limit exceeded. Only ' + options.arrayLimit + ' element' + (options.arrayLimit === 1 ? '' : 's') + ' allowed in an array.'); } return val; ``` This aligns behavior with indexed and bracket notations, reuses `currentArrayLength`, and respects `throwOnLimitExceeded`. Update README to note the consistent enforcement. |
Affected by 0 other vulnerabilities. |
| Vulnerability | Summary | Aliases |
|---|---|---|
| VCID-3nf9-4fhn-fkg9 | Improper Input Validation The qs module is vulnerable to a DoS. A malicious user can send an evil request to cause the web framework crash. |
CVE-2017-1000048
GHSA-gqgv-6jq5-jjj9 |