Security advisory
Prototype poisoning in function mapObjIndexed in Ramda 0.27.0 and earlier allows attackers to compromise integrity or availability of application via supplying a crafted object (that contains an own property "__proto__") as an argument to the function. NOTE: the vendor disputes this because the observed behavior only means that a user can create objects that the user didn't know would contain custom prototypes
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-42581
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 11:59 UTC · Revision 1
Source evidence
Prototype poisoning in function mapObjIndexed in Ramda 0.27.0 and earlier allows attackers to compromise integrity or availability of application via supplying a crafted object (that contains an own property "__proto__") as an argument to the function. NOTE: the vendor disputes this because the observed behavior only means that a user can create objects that the user didn't know would contain custom prototypes
osv:CVE-2021-42581
Complete source record
{
"id": "d757b47419f294192a28539e9019232df74da0ffa3703cf799976d68a81fc454",
"url": "https://osv.dev/vulnerability/CVE-2021-42581",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-42581",
"summary": "Prototype poisoning in function mapObjIndexed in Ramda 0.27.0 and earlier allows attackers to compromise integrity or availability of application via supplying a crafted object (that contains an own property \"__proto__\") as an argument to the function. NOTE: the vendor disputes this because the observed behavior only means that a user can create objects that the user didn't know would contain custom prototypes",
"evidence": "osv:CVE-2021-42581",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-42581",
"aliases": [
"CVE-2021-42581"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/ramda/ramda",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "ed191e6a476330e37db259a5c2d04bfba0b2d63d"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:ramdajs:ramda:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "0.27.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v0.27.0",
"0.26.1",
"v0.26.1",
"v0.26.0",
"0.26.0",
"v0.25.0",
"v0.24.1",
"v0.24.0",
"v0.23.0",
"v0.22.1",
"v0.22.0",
"v0.21.0",
"v0.20.1",
"v0.20.0",
"v0.19.1",
"v0.19.0",
"v0.18.0",
"v0.17.1",
"v0.17.0",
"v0.16.0",
"v0.15.1",
"v0.15.0",
"v0.14.0",
"v0.13.0",
"v0.12.0",
"v0.11.0",
"v0.10.0",
"v0.9.1",
"v0.9.0",
"v0.8.0",
"v0.7.2",
"v0.7.1",
"v0.7.0",
"v0.6.0",
"v0.5.0",
"v0.4.3",
"v0.4.2",
"v0.4.0",
"v0.3.0",
"v0.2.4",
"v0.2.3",
"v0.2.1",
"v0.1.5",
"v0.1.4",
"v0.1.3",
"v0.1.2",
"v0.1.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-42581.json"
}
}
],
"modified": "2026-10-20T10:55:01.402131132Z",
"provider": "osv",
"references": [
"https://github.com/ramda/ramda/pull/3192",
"https://jsfiddle.net/3pomzw5g/2/"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-42581",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 386705,
"published_at": "2022-05-10T11:15:07.97+00:00"
}