CVE-2026-82417 (GCVE-0-2026-82417)
Vulnerability from cvelistv5 – Published: 2026-08-29 23:51 – Updated: 2026-08-31 17:08
VLAI
EPSS
VEX
Title
qs.stringify throws TypeError on objects with a non-callable constructor.isBuffer property
Summary
### Summary
`qs.stringify` throws a `TypeError` when it serializes an object whose own `constructor` property has a truthy, non-callable `isBuffer` member. `utils.isBuffer` duck-types buffers by calling `obj.constructor.isBuffer(obj)` after checking only that the property is truthy, so a value such as `{ constructor: { isBuffer: "x" } }` makes the call throw `TypeError: obj.constructor.isBuffer is not a function`.
### Details
`lib/stringify.js:127` calls `utils.isBuffer` on every non-primitive value it serializes. `utils.isBuffer` (`lib/utils.js:332`) reads `obj.constructor.isBuffer` and invokes it without verifying that it is a function. `constructor` and `isBuffer` are ordinary property names, so any object carrying them as own properties reaches the unchecked call.
Such an object can be built from untrusted input. `qs.parse("x[constructor][isBuffer]=y", { plainObjects: true })` or `{ allowPrototypes: true }` keeps the `constructor` key as an own property (the default parse options drop it), and `JSON.parse("{\"a\":{\"constructor\":{\"isBuffer\":\"x\"}}}")` produces the same shape with no qs option involved. Express 4 with its default `query parser` setting and body-parser with `extended: true` both call `qs.parse` with `allowPrototypes: true`, so on those stacks `req.query` and `req.body` can carry the shape directly.
#### PoC
```js
var qs = require("qs");
qs.stringify(qs.parse("x[constructor][isBuffer]=y", { plainObjects: true }));
qs.stringify(JSON.parse("{\"a\":{\"constructor\":{\"isBuffer\":\"x\"}}}"));
// TypeError: obj.constructor.isBuffer is not a function
// at Object.isBuffer (lib/utils.js:332:78)
// at stringify (lib/stringify.js:127:45)
```
#### Fix
`lib/utils.js`, applied in e83d321 on `main` and released as v6.16.0:
```diff
- return !!(obj.constructor && obj.constructor.isBuffer && obj.constructor.isBuffer(obj));
+ return !!(obj.constructor && typeof obj.constructor.isBuffer === "function" && obj.constructor.isBuffer(obj));
```
Real `Buffer`, `safer-buffer`, and browserify `buffer` polyfill instances serialize exactly as before; only the throw is removed.
### Affected versions
`>=2.2.5 <6.16.0`, fixed in v6.16.0.
The unguarded duck-type was introduced in 3768a75 and first shipped in v2.2.5 (September 2014). v2.2.4 and earlier used `Buffer.isBuffer` and are not affected. Every release from v2.2.5 through v6.15.3 contains the unguarded call.
### Impact
An unauthenticated request can make any code path that re-serializes attacker-influenced data with `qs.stringify` (for example, rebuilding a query string from `req.query` for a redirect or an upstream request, or serializing a parsed JSON body) throw synchronously. In a typical Node.js HTTP framework the throw is caught by the framework error boundary and the affected request returns a 500; the process survives and other requests are unaffected. Where the call runs outside an error boundary, such as an `async` Express 4 handler (where the throw becomes an unhandled promise rejection) or a background job, the process exits, so the impact in that case depends on the application error handling rather than on qs.
Severity
5.3 (Medium)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-31 17:07 UTC
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/ljharb/qs/security/advisories/… | vendor-advisory |
| https://github.com/ljharb/qs/commit/e83d321ffafb3… | patch |
Impacted products
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"value": "\u003cp\u003e### Summary\u003c/p\u003e\u003cp\u003e`qs.stringify` throws a `TypeError` when it serializes an object whose own `constructor` property has a truthy, non-callable `isBuffer` member. `utils.isBuffer` duck-types buffers by calling `obj.constructor.isBuffer(obj)` after checking only that the property is truthy, so a value such as `{ constructor: { isBuffer: \"x\" } }` makes the call throw `TypeError: obj.constructor.isBuffer is not a function`.\u003c/p\u003e\u003cp\u003e### Details\u003c/p\u003e\u003cp\u003e`lib/stringify.js:127` calls `utils.isBuffer` on every non-primitive value it serializes. `utils.isBuffer` (`lib/utils.js:332`) reads `obj.constructor.isBuffer` and invokes it without verifying that it is a function. `constructor` and `isBuffer` are ordinary property names, so any object carrying them as own properties reaches the unchecked call.\u003c/p\u003e\u003cp\u003eSuch an object can be built from untrusted input. `qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true })` or `{ allowPrototypes: true }` keeps the `constructor` key as an own property (the default parse options drop it), and `JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\")` produces the same shape with no qs option involved. Express 4 with its default `query parser` setting and body-parser with `extended: true` both call `qs.parse` with `allowPrototypes: true`, so on those stacks `req.query` and `req.body` can carry the shape directly.\u003c/p\u003e\u003cp\u003e#### PoC\u003c/p\u003e\u003cp\u003e```js\u003c/p\u003e\u003cp\u003evar qs = require(\"qs\");\u003c/p\u003e\u003cp\u003eqs.stringify(qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true }));\u003c/p\u003e\u003cp\u003eqs.stringify(JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\"));\u003c/p\u003e\u003cp\u003e// TypeError: obj.constructor.isBuffer is not a function\u003c/p\u003e\u003cp\u003e// at Object.isBuffer (lib/utils.js:332:78)\u003c/p\u003e\u003cp\u003e// at stringify (lib/stringify.js:127:45)\u003c/p\u003e\u003cp\u003e```\u003c/p\u003e\u003cp\u003e#### Fix\u003c/p\u003e\u003cp\u003e`lib/utils.js`, applied in e83d321 on `main` and released as v6.16.0:\u003c/p\u003e\u003cp\u003e```diff\u003c/p\u003e\u003cp\u003e- return !!(obj.constructor \u0026amp;\u0026amp; obj.constructor.isBuffer \u0026amp;\u0026amp; obj.constructor.isBuffer(obj));\u003c/p\u003e\u003cp\u003e+ return !!(obj.constructor \u0026amp;\u0026amp; typeof obj.constructor.isBuffer === \"function\" \u0026amp;\u0026amp; obj.constructor.isBuffer(obj));\u003c/p\u003e\u003cp\u003e```\u003c/p\u003e\u003cp\u003eReal `Buffer`, `safer-buffer`, and browserify `buffer` polyfill instances serialize exactly as before; only the throw is removed.\u003c/p\u003e\u003cp\u003e### Affected versions\u003c/p\u003e\u003cp\u003e`\u0026gt;=2.2.5 \u0026lt;6.16.0`, fixed in v6.16.0.\u003c/p\u003e\u003cp\u003eThe unguarded duck-type was introduced in 3768a75 and first shipped in v2.2.5 (September 2014). v2.2.4 and earlier used `Buffer.isBuffer` and are not affected. Every release from v2.2.5 through v6.15.3 contains the unguarded call.\u003c/p\u003e\u003cp\u003e### Impact\u003c/p\u003e\u003cp\u003eAn unauthenticated request can make any code path that re-serializes attacker-influenced data with `qs.stringify` (for example, rebuilding a query string from `req.query` for a redirect or an upstream request, or serializing a parsed JSON body) throw synchronously. In a typical Node.js HTTP framework the throw is caught by the framework error boundary and the affected request returns a 500; the process survives and other requests are unaffected. Where the call runs outside an error boundary, such as an `async` Express 4 handler (where the throw becomes an unhandled promise rejection) or a background job, the process exits, so the impact in that case depends on the application error handling rather than on qs.\u003c/p\u003e"
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"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"version": "4.0",
"vulnAvailabilityImpact": "LOW",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"source": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-82417",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-08-31T17:07:54.823942Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-08-30T00:16:34.657",
"references": [
{
"source": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"url": "https://github.com/ljharb/qs/commit/e83d321ffafb38cf210683ac31714fce6ce1c6c6"
},
{
"source": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"url": "https://github.com/ljharb/qs/security/advisories/GHSA-4mjr-xmp4-gh2g"
},
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"url": "https://github.com/ljharb/qs/security/advisories/GHSA-4mjr-xmp4-gh2g"
}
],
"sourceIdentifier": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-248"
},
{
"lang": "en",
"value": "CWE-703"
}
],
"source": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Important",
"current_release_date": "2026-09-21T16:34:31+00:00",
"cve": "CVE-2026-82417",
"id": "CVE-2026-82417",
"initial_release_date": "2026-08-29T23:51:27.634000+00:00",
"product_status:fixed": "25",
"product_status:known_affected": "279",
"product_status:known_not_affected": "207",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "qs: qs: Denial of Service via improper validation in stringify function",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-82417.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-09-03T16:24:32Z",
"cve": "CVE-2026-82417",
"id": "CVE-2026-82417",
"initial_release_date": "2026-09-03T16:24:32Z",
"product_status:known_affected": "201",
"product_status:known_not_affected": "342",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-82417",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-82417.json",
"version": "2"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-82417",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-08-31T17:07:54.823942Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-08-31T17:08:19.341Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"exploit"
],
"url": "https://github.com/ljharb/qs/security/advisories/GHSA-4mjr-xmp4-gh2g"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://npmjs.com/qs",
"defaultStatus": "unaffected",
"packageName": "qs",
"product": "qs",
"repo": "https://github.com/ljharb/qs",
"vendor": "ljharb",
"versions": [
{
"lessThan": "6.16.0",
"status": "affected",
"version": "2.2.5",
"versionType": "semver"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "waydeshi"
},
{
"lang": "en",
"type": "remediation developer",
"value": "ljharb"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cp\u003e### Summary\u003c/p\u003e\u003cp\u003e`qs.stringify` throws a `TypeError` when it serializes an object whose own `constructor` property has a truthy, non-callable `isBuffer` member. `utils.isBuffer` duck-types buffers by calling `obj.constructor.isBuffer(obj)` after checking only that the property is truthy, so a value such as `{ constructor: { isBuffer: \"x\" } }` makes the call throw `TypeError: obj.constructor.isBuffer is not a function`.\u003c/p\u003e\u003cp\u003e### Details\u003c/p\u003e\u003cp\u003e`lib/stringify.js:127` calls `utils.isBuffer` on every non-primitive value it serializes. `utils.isBuffer` (`lib/utils.js:332`) reads `obj.constructor.isBuffer` and invokes it without verifying that it is a function. `constructor` and `isBuffer` are ordinary property names, so any object carrying them as own properties reaches the unchecked call.\u003c/p\u003e\u003cp\u003eSuch an object can be built from untrusted input. `qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true })` or `{ allowPrototypes: true }` keeps the `constructor` key as an own property (the default parse options drop it), and `JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\")` produces the same shape with no qs option involved. Express 4 with its default `query parser` setting and body-parser with `extended: true` both call `qs.parse` with `allowPrototypes: true`, so on those stacks `req.query` and `req.body` can carry the shape directly.\u003c/p\u003e\u003cp\u003e#### PoC\u003c/p\u003e\u003cp\u003e```js\u003c/p\u003e\u003cp\u003evar qs = require(\"qs\");\u003c/p\u003e\u003cp\u003eqs.stringify(qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true }));\u003c/p\u003e\u003cp\u003eqs.stringify(JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\"));\u003c/p\u003e\u003cp\u003e// TypeError: obj.constructor.isBuffer is not a function\u003c/p\u003e\u003cp\u003e// at Object.isBuffer (lib/utils.js:332:78)\u003c/p\u003e\u003cp\u003e// at stringify (lib/stringify.js:127:45)\u003c/p\u003e\u003cp\u003e```\u003c/p\u003e\u003cp\u003e#### Fix\u003c/p\u003e\u003cp\u003e`lib/utils.js`, applied in e83d321 on `main` and released as v6.16.0:\u003c/p\u003e\u003cp\u003e```diff\u003c/p\u003e\u003cp\u003e- return !!(obj.constructor \u0026amp;\u0026amp; obj.constructor.isBuffer \u0026amp;\u0026amp; obj.constructor.isBuffer(obj));\u003c/p\u003e\u003cp\u003e+ return !!(obj.constructor \u0026amp;\u0026amp; typeof obj.constructor.isBuffer === \"function\" \u0026amp;\u0026amp; obj.constructor.isBuffer(obj));\u003c/p\u003e\u003cp\u003e```\u003c/p\u003e\u003cp\u003eReal `Buffer`, `safer-buffer`, and browserify `buffer` polyfill instances serialize exactly as before; only the throw is removed.\u003c/p\u003e\u003cp\u003e### Affected versions\u003c/p\u003e\u003cp\u003e`\u0026gt;=2.2.5 \u0026lt;6.16.0`, fixed in v6.16.0.\u003c/p\u003e\u003cp\u003eThe unguarded duck-type was introduced in 3768a75 and first shipped in v2.2.5 (September 2014). v2.2.4 and earlier used `Buffer.isBuffer` and are not affected. Every release from v2.2.5 through v6.15.3 contains the unguarded call.\u003c/p\u003e\u003cp\u003e### Impact\u003c/p\u003e\u003cp\u003eAn unauthenticated request can make any code path that re-serializes attacker-influenced data with `qs.stringify` (for example, rebuilding a query string from `req.query` for a redirect or an upstream request, or serializing a parsed JSON body) throw synchronously. In a typical Node.js HTTP framework the throw is caught by the framework error boundary and the affected request returns a 500; the process survives and other requests are unaffected. Where the call runs outside an error boundary, such as an `async` Express 4 handler (where the throw becomes an unhandled promise rejection) or a background job, the process exits, so the impact in that case depends on the application error handling rather than on qs.\u003c/p\u003e"
}
],
"value": "### Summary\n\n\n\n`qs.stringify` throws a `TypeError` when it serializes an object whose own `constructor` property has a truthy, non-callable `isBuffer` member. `utils.isBuffer` duck-types buffers by calling `obj.constructor.isBuffer(obj)` after checking only that the property is truthy, so a value such as `{ constructor: { isBuffer: \"x\" } }` makes the call throw `TypeError: obj.constructor.isBuffer is not a function`.\n\n\n\n### Details\n\n\n\n`lib/stringify.js:127` calls `utils.isBuffer` on every non-primitive value it serializes. `utils.isBuffer` (`lib/utils.js:332`) reads `obj.constructor.isBuffer` and invokes it without verifying that it is a function. `constructor` and `isBuffer` are ordinary property names, so any object carrying them as own properties reaches the unchecked call.\n\n\n\nSuch an object can be built from untrusted input. `qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true })` or `{ allowPrototypes: true }` keeps the `constructor` key as an own property (the default parse options drop it), and `JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\")` produces the same shape with no qs option involved. Express 4 with its default `query parser` setting and body-parser with `extended: true` both call `qs.parse` with `allowPrototypes: true`, so on those stacks `req.query` and `req.body` can carry the shape directly.\n\n\n\n#### PoC\n\n\n\n```js\n\n\n\nvar qs = require(\"qs\");\n\n\n\nqs.stringify(qs.parse(\"x[constructor][isBuffer]=y\", { plainObjects: true }));\n\n\n\nqs.stringify(JSON.parse(\"{\\\"a\\\":{\\\"constructor\\\":{\\\"isBuffer\\\":\\\"x\\\"}}}\"));\n\n\n\n// TypeError: obj.constructor.isBuffer is not a function\n\n\n\n// at Object.isBuffer (lib/utils.js:332:78)\n\n\n\n// at stringify (lib/stringify.js:127:45)\n\n\n\n```\n\n\n\n#### Fix\n\n\n\n`lib/utils.js`, applied in e83d321 on `main` and released as v6.16.0:\n\n\n\n```diff\n\n\n\n- return !!(obj.constructor \u0026\u0026 obj.constructor.isBuffer \u0026\u0026 obj.constructor.isBuffer(obj));\n\n\n\n+ return !!(obj.constructor \u0026\u0026 typeof obj.constructor.isBuffer === \"function\" \u0026\u0026 obj.constructor.isBuffer(obj));\n\n\n\n```\n\n\n\nReal `Buffer`, `safer-buffer`, and browserify `buffer` polyfill instances serialize exactly as before; only the throw is removed.\n\n\n\n### Affected versions\n\n\n\n`\u003e=2.2.5 \u003c6.16.0`, fixed in v6.16.0.\n\n\n\nThe unguarded duck-type was introduced in 3768a75 and first shipped in v2.2.5 (September 2014). v2.2.4 and earlier used `Buffer.isBuffer` and are not affected. Every release from v2.2.5 through v6.15.3 contains the unguarded call.\n\n\n\n### Impact\n\n\n\nAn unauthenticated request can make any code path that re-serializes attacker-influenced data with `qs.stringify` (for example, rebuilding a query string from `req.query` for a redirect or an upstream request, or serializing a parsed JSON body) throw synchronously. In a typical Node.js HTTP framework the throw is caught by the framework error boundary and the affected request returns a 500; the process survives and other requests are unaffected. Where the call runs outside an error boundary, such as an `async` Express 4 handler (where the throw becomes an unhandled promise rejection) or a background job, the process exits, so the impact in that case depends on the application error handling rather than on qs."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 5.3,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 6.3,
"baseSeverity": "MEDIUM",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "LOW",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-248",
"description": "CWE-248 Uncaught Exception",
"lang": "en",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-703",
"description": "CWE-703 Improper Check or Handling of Exceptional Conditions",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-29T23:51:27.634Z",
"orgId": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"shortName": "harborist"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://github.com/ljharb/qs/security/advisories/GHSA-4mjr-xmp4-gh2g"
},
{
"tags": [
"patch"
],
"url": "https://github.com/ljharb/qs/commit/e83d321ffafb38cf210683ac31714fce6ce1c6c6"
}
],
"solutions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cp\u003eUpgrade to qs 6.16.0 or later.\u003c/p\u003e"
}
],
"value": "Upgrade to qs 6.16.0 or later."
}
],
"source": {
"discovery": "EXTERNAL"
},
"title": "qs.stringify throws TypeError on objects with a non-callable constructor.isBuffer property",
"workarounds": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cp\u003ePass a `filter` function to `qs.stringify` that drops values carrying an own `constructor` property; it runs before the `isBuffer` check. Alternatively, wrap `qs.stringify` calls on externally influenced objects in try/catch, and avoid `allowPrototypes: true` / `plainObjects: true` when parsed untrusted input is fed back into `qs.stringify`.\u003c/p\u003e"
}
],
"value": "Pass a `filter` function to `qs.stringify` that drops values carrying an own `constructor` property; it runs before the `isBuffer` check. Alternatively, wrap `qs.stringify` calls on externally influenced objects in try/catch, and avoid `allowPrototypes: true` / `plainObjects: true` when parsed untrusted input is fed back into `qs.stringify`."
}
]
}
},
"cveMetadata": {
"assignerOrgId": "7ffcee3d-2c14-4c3e-b844-86c6a321a158",
"assignerShortName": "harborist",
"cveId": "CVE-2026-82417",
"datePublished": "2026-08-29T23:51:27.634Z",
"dateReserved": "2026-08-28T23:08:00.460Z",
"dateUpdated": "2026-08-31T17:08:24.074Z",
"state": "PUBLISHED"
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"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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