GHSA-525M-7F82-2MF7
Vulnerability from github – Published: 2026-07-02 19:18 – Updated: 2026-07-02 19:18A CPU exhaustion vulnerability exists in Conform's parseSubmission future API when parsing FormData or URLSearchParams submissions with many unique field names. The parser previously looked up values by field name, which could require repeated scans of the submitted entries and cause excessive synchronous CPU work if an attacker supplies a crafted submission.
[!NOTE] The patched version fixes this by iterating submitted entries directly instead of repeatedly looking up values by field name. Applications that accept untrusted form submissions should still enforce request parsing limits before passing data to Conform. For multipart requests, @remix-run/form-data-parser provides
maxParts,maxTotalSize,maxFileSize,maxFiles, andmaxHeaderSizeoptions.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "@conform-to/dom"
},
"ranges": [
{
"events": [
{
"introduced": "1.8.0"
},
{
"fixed": "1.19.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-49250"
],
"database_specific": {
"cwe_ids": [
"CWE-407"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-02T19:18:41Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "A CPU exhaustion vulnerability exists in Conform\u0027s [`parseSubmission`](https://conform.guide/api/react/future/parseSubmission) future API when parsing `FormData` or `URLSearchParams` submissions with many unique field names. The parser previously looked up values by field name, which could require repeated scans of the submitted entries and cause excessive synchronous CPU work if an attacker supplies a crafted submission.\n\n\u003e [!NOTE]\n\u003e The patched version fixes this by iterating submitted entries directly instead of repeatedly looking up values by field name. Applications that accept untrusted form submissions should still enforce request parsing limits before passing data to Conform. For multipart requests, [@remix-run/form-data-parser](https://www.npmjs.com/package/@remix-run/form-data-parser) provides `maxParts`, `maxTotalSize`, `maxFileSize`, `maxFiles`, and `maxHeaderSize` options.",
"id": "GHSA-525m-7f82-2mf7",
"modified": "2026-07-02T19:18:41Z",
"published": "2026-07-02T19:18:41Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/edmundhung/conform/security/advisories/GHSA-525m-7f82-2mf7"
},
{
"type": "PACKAGE",
"url": "https://github.com/edmundhung/conform"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "@conform-to/dom parseSubmission vulnerable to CPU exhaustion when parsing many unique form fields"
}
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.