GHSA-6rw7-vpxm-498p · Severity: medium · Ecosystem: npm — qs's arrayLimit bypass in its bracket notation allows DoS via memory exhaustion
Improper Input Validation vulnerability in qs (parse modules) allows HTTP DoS.This issue affects qs: < 6.14.1. Summary 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[]=valueconsumes one parameter slot. The severity has been reduced accordingly. Details The arrayLimit option only checked limits for indexed notation (a[0]=1&a[1]=2) but did not enforce it for bracket notation (a[]=1&a[]=2). Vulnerable code (lib/parse.js:159-162): if (root === '[]' && options.parseArrays) { obj = utils.combine([], leaf); // No arrayLimit check } Working code (lib/parse.js:175): else if (index <= options.arrayLimit) { // Limit checked here obj = []; obj[index] = leaf; } The bracket notation handler at line 159 uses utils.combine([], leaf) without validating against options.arrayLimit, while indexed notation at line 175 checks index <= options.arrayLimit before creating arrays. PoC const qs = require('qs'); const result = qs.parse('a[]=1&a[]=2&a[]=3&a[]=4&a[]=5&a[]=6', { arrayLimit: 5 }); console.log(result.a.length); // Output: 6 (should be max 5) Note on parameterLimit interaction: The original advisory's "DoS demonstration" claimed a length of 10,000, but parameterLimit (default: 1000) caps parsing to 1,000 parameters. With default options, the actual output is 1,000, not 10,000. Impact Consistency bug in arrayLimit enforcement. With default parameterLimit, the practical DoS risk is negligible since parameterLimit already caps the total number of parsed parameters (and thus array elements from bracket notation). The risk increases only when parameterLimit is explicitly set to a very high value.
Conclusion & alert: CVE-2025-15284 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.04%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-27 | 0.06% | 0.04% | -0.02% |
| 2 | 2026-03-21 | 0.22% | 0.06% | -0.16% |
| 3 | 2026-02-27 | — | 0.22% | — |
Full EPSS history (6 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.3 | 4.0 | MEDIUM |
|
— | — | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 |
| 3.7 | 3.1 | LOW |
|
2.2 | 1.4 | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 |
GHSA-6rw7-vpxm-498p · Severity: medium · Ecosystem: npm — qs's arrayLimit bypass in its bracket notation allows DoS via memory exhaustion
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2025-15284 not yet assigned priority: Debian including 1 source packages (node-qs), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. | https://security-tracker.debian.org/tracker/CVE-2025-15284 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2025-15284 |
ubuntu
|
medium | CVE-2025-15284 medium priority: Ubuntu including 1 source packages (node-qs), 9 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): needs-triage 7, ignored 1, released 1. | https://ubuntu.com/security/CVE-2025-15284 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| qs_project | qs | < 6.14.1 | cpe:2.3:a:qs_project:qs:*:*:*:*:*:node.js:*:* |
| URL | Tags |
|---|---|
| https://github.com/ljharb/qs/commit/3086902ecf7f088d0d1803887643ac6c03d415b9 | Patch |
| https://github.com/ljharb/qs/security/advisories/GHSA-6rw7-vpxm-498p | Exploit Mitigation Vendor Advisory |