node-lodash — security advisory
The fix for CVE-2021-23337 added validation for the variable option in _.template but did not apply the same validation to options.imports key names, and both paths flow into the same Function() constructor sink. When an application passes untrusted input as options.imports key names, an attacker can inject default-parameter expressions that execute arbitrary code at template compilation time. Additionally, _.template uses assignInWith to merge imports, which enumerates inherited properties via for..in, so if Object.prototype has been polluted by another vector the polluted keys are copied into the imports object and passed to Function(). The issue is fixed in 4.18.1 for lodash, lodash-es, lodash-amd, and lodash.template. As a workaround, do not pass untrusted input as key names in options.imports; use only developer-controlled, static key names.
- Products
- node-lodash
- Affected versions
- 4.17.21+dfsg+~cs8.31.198.20210220-10, 4.17.21+dfsg+~cs8.31.198.20210220-9, 4.17.23+dfsg-1
- Fixed versions
- 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1, 4.17.21+dfsg+~cs8.31.198.20210220-9+deb13u1, 4.18.1+dfsg-1
- CVEs
- CVE-2026-4800
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 19:59 UTC · Revision 1
Source evidence
The fix for CVE-2021-23337 added validation for the variable option in _.template but did not apply the same validation to options.imports key names, and both paths flow into the same Function() constructor sink. When an application passes untrusted input as options.imports key names, an attacker can inject default-parameter expressions that execute arbitrary code at template compilation time. Additionally, _.template uses assignInWith to merge imports, which enumerates inherited properties via for..in, so if Object.prototype has been polluted by another vector the polluted keys are copied into the imports object and passed to Function(). The issue is fixed in 4.18.1 for lodash, lodash-es, lodash-amd, and lodash.template. As a workaround, do not pass untrusted input as key names in options.imports; use only developer-controlled, static key names.
osv:DEBIAN-CVE-2026-4800
node-lodash
Fixed versions: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1
node-lodash
Fixed versions: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb13u1
node-lodash
Fixed versions: 4.18.1+dfsg-1
Complete source record
{
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"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-4800",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-4800",
"summary": "The fix for CVE-2021-23337 added validation for the variable option in _.template but did not apply the same validation to options.imports key names, and both paths flow into the same Function() constructor sink. When an application passes untrusted input as options.imports key names, an attacker can inject default-parameter expressions that execute arbitrary code at template compilation time. Additionally, _.template uses assignInWith to merge imports, which enumerates inherited properties via for..in, so if Object.prototype has been polluted by another vector the polluted keys are copied into the imports object and passed to Function(). The issue is fixed in 4.18.1 for lodash, lodash-es, lodash-amd, and lodash.template. As a workaround, do not pass untrusted input as key names in options.imports; use only developer-controlled, static key names.",
"evidence": "osv:DEBIAN-CVE-2026-4800",
"products": [
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{
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"aliases": [
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"metrics": [
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}
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],
"modified": "2026-10-16T09:47:34.393898316Z",
"provider": "osv",
"upstream": [
"CVE-2026-4800"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-4800"
]
},
"related_cves": [
{
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"evidence": "/upstream"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 338646,
"published_at": "2026-03-31T20:16:29.66+00:00"
}