CVSS 4.0
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Атакува се по мрежата, без особени условия, само при определена конфигурация или състояние на системата, без вход и без действие от потребителя.
- Експлоатация: има публичен пример за експлоатация
- Атаката може да се автоматизира
Описание
Оригинално описание
### 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
Засегнати продукти
- ljharb qs: 6.11.1 преди 6.15.2
Вид слабост
История
- 16 май 2026 Публикувано