GHSA-q8mj-m7cp-5q26 · 深刻度： medium · エコシステム： npm — qs has a remotely triggerable DoS: qs.stringify crashes with TypeError on null/undefined entries in comma-format arrays when encodeValuesOnly is set
### Summary `qs.stringify` throws `TypeError` when called with `arrayFormat: 'comma'` and `encodeValuesOnly: true` on an array containing `null` or `undefined`. The throw is synchronous and not handled by any of qs's null-related options (`skipNulls`, `strictNullHandling`). ### Details In the comma + `encodeValuesOnly` branch, `lib/stringify.js:145` mapped the array through the raw encoder before joining: ```js obj = utils.maybeMap(obj, encoder); ``` `utils.encode` (`lib/utils.js:195`) reads `str.length` with no null guard, so a `null` or `undefined` element throws `TypeError`. `skipNulls` and `strictNullHandling` are both checked in the per-element loop below this line and never get a chance to run. Same class of bug as the filter-array path fixed in 0c180a4. The vulnerable shape of the comma + `encodeValuesOnly` branch was introduced in 4c4b23d ("encode comma values more consistently", PR #463, 2023-01-19), first released in v6.11.1. #### PoC ```js const qs = require('qs'); qs.stringify({ a: [null, 'b'] }, { arrayFormat: 'comma', encodeValuesOnly: true }); qs.stringify({ a: [undefined, 'b'] }, { arrayFormat: 'comma', encodeValuesOnly: true }); qs.stringify({ a: [null] }, { arrayFormat: 'comma', encodeValuesOnly: true }); // TypeError: Cannot read properties of null (reading 'length') // at encode (lib/utils.js:195:13) // at Object.maybeMap (lib/utils.js:322:37) // at stringify (lib/stringify.js:145:25) ``` #### Fix `lib/stringify.js:145`, applied in 21f80b3 on `main` and released as v6.15.2: ```diff - obj = utils.maybeMap(obj, encoder); + obj = utils.maybeMap(obj, function (v) { + return v == null ? v : encoder(v); + }); ``` `null` and `undefined` now pass through `maybeMap` unchanged and reach the `join(',')` step as-is. For `{ a: [null, 'b'] }` this produces `a=,b`, matching the non-`encodeValuesOnly` comma path (which already joins before encoding and produces `a=%2Cb` for the same input). Single-element `[null]` arrays still collapse via the existing `obj.join(',') || null` and remain subject to `skipNulls` / `strictNullHandling` in the main loop. ### Affected versions `>=6.11.1 <6.15.2` — fixed in v6.15.2. The vulnerable code shape was introduced in 4c4b23d and first shipped in v6.11.1. Earlier versions — including all of 6.7.x, 6.8.x, 6.9.x, 6.10.x, and 6.11.0 — implemented the comma + `encodeValuesOnly` path differently (joining before encoding) and are not affected. Empirically verified across released versions. ### Impact Application code that calls `qs.stringify` with both `arrayFormat: 'comma'` and `encodeValuesOnly: true` (both non-default) on input that may contain a `null` or `undefined` array element will throw synchronously instead of producing a query string. In a typical Node.js HTTP framework (Express, Fastify, Koa, hapi) the sync throw is caught by the framework's error boundary and the affected request returns a 500; the worker process does not exit and subsequent requests are unaffected. The "kills the worker process" framing applies only to call sites outside a request-handler error boundary (background jobs, startup paths, stream pipelines) or to deployments with framework error handling explicitly disabled. The vulnerable input is a `null` or `undefined` entry inside an array; this is reachable from JSON request bodies or from application code constructing arrays from user input, but not from standard HTML form submissions (which produce strings or omitted fields, not literal `null`).
総合評価: CVE-2026-8723 は低リスク（34.7/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.35%、27 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-23 | 0.27% | 0.35% | +0.08% |
| 2 | 2026-06-15 | 0.03% | 0.27% | +0.23% |
| 3 | 2026-05-17 | — | 0.03% | — |
EPSS の全履歴 （全 3 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 6.3 | 4.0 | MEDIUM |
|
— | — | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 |
| 5.3 | 3.1 | MEDIUM |
|
3.9 | 1.4 | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 |
GHSA-q8mj-m7cp-5q26 · 深刻度： medium · エコシステム： npm — qs has a remotely triggerable DoS: qs.stringify crashes with TypeError on null/undefined entries in comma-format arrays when encodeValuesOnly is set
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-8723 not yet assigned priority: Debian including 1 source packages (node-qs), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 4, resolved 1. | https://security-tracker.debian.org/tracker/CVE-2026-8723 |
ubuntu
|
medium | CVE-2026-8723 medium priority: Ubuntu including 1 source packages (node-qs), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream): needs-triage 8. | https://ubuntu.com/security/CVE-2026-8723 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| データセットに影響を受ける製品はありません。 | |||