CVE-2026-4800

CVE Enrichment

CVSS: 9.8 CRITICAL
EPSS: 2.62%
EPSS Percentile: 85.35%
CISA KEV: Not listed

Description

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.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: ce714d77-add3-4f53-aff5-83d477b104bb
Published: 01-Apr-2026 03:16
Last Modified: 15-Oct-2026 14:18
EPSS Date: 2026-10-24
CWE: CWE-94

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:H /
                            I:H /
                            A:H

Affected Products / Versions

lodash / lodash
Version / affected range: * · from (inclusive) 4.0.0 · before (exclusive) 4.18.0
cpe:2.3:a:lodash:lodash:*:*:*:*:*:node.js:*:*
lodash / lodash-amd
Version / affected range: * · from (inclusive) 4.0.0 · before (exclusive) 4.18.0
cpe:2.3:a:lodash:lodash-amd:*:*:*:*:*:node.js:*:*
lodash / lodash-es
Version / affected range: * · from (inclusive) 4.0.0 · before (exclusive) 4.18.0
cpe:2.3:a:lodash:lodash-es:*:*:*:*:*:node.js:*:*
lodash / lodash.template
Version / affected range: * · from (inclusive) 4.0.0 · before (exclusive) 4.18.0
cpe:2.3:a:lodash:lodash.template:*:*:*:*:*:node.js:*:*

References

Last enrichment sync: 25-Oct-2026 00:31
Sources: NVD · FIRST EPSS · CISA KEV
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Reported Context (1)

Lodash's 2021 fix added validation for the variable option but missed options.imports key names, which feed the same Function() constructor. That second path became CVE-2026-4800, fixed in lodash 4.18.0. Reachable CVEs Aren’t Always Exploitable: How App Context Changes Risk

CVE (1)

Vendors (1)

Products (3)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.