dbcve.org
LodashApplication

CVE-2026-2950

MEDIUM · 5.3 CVSS v3.1 Published 2026-03-31
Fix available
A fix is available. Upgrade to 4.17.23 or later.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Impact: Lodash versions 4.17.23 and earlier are vulnerable to prototype pollution in the _.unset and _.omit functions. The fix for (CVE-2025-13465: https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg) only guards against string key members, so an attacker can bypass the check by passing array-wrapped path segments. This allows deletion of properties from built-in prototypes such as Object.prototype, Number.prototype, and String.prototype. The issue permits deletion of prototype properties but does not allow overwriting their original behavior. Patches: This issue is patched in 4.18.0. Workarounds: None. Upgrade to the patched version.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Lodash versions 4.17.23 and earlier contain a prototype pollution vulnerability in _.unset and _.omit functions. The prior fix (CVE-2025-13465) only blocked string key members, allowing attackers to bypass the check using array-wrapped path segments like ['__proto__']. This enables deletion of properties from built-in prototypes (Object.prototype, Number.prototype, String.prototype), though it does not permit overwriting prototype behavior.

MitigationUpgrade lodash to version 4.18.0 or later to patch the vulnerability. There are no workarounds; applications using _.unset or _.omit with user-controlled paths are vulnerable.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
LodashApplication
Affected:>= 4.0.0, < 4.17.23
Lodash AmdApplication
Affected:>= 4.0.0, < 4.17.23
Lodash EsApplication
Affected:>= 4.0.0, < 4.17.23
Lodash.unsetApplication
Affected:>= 4.0.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Lodash version
    Run 'npm list lodash' or inspect the version field in node_modules/lodash/package.json, or execute require('lodash/package.json').version in Node.js
    Affected if Version is 4.0.0 or higher but below 4.17.23
  2. Verify vulnerable functions are in use
    Search your codebase for usage of _.unset and _.omit methods, for example: _.unset(obj, path), _.omit(obj, path), or their lodash.unset/lodash.omit equivalents
    Affected if Codebase contains calls to _.unset or _.omit where the path argument can be influenced by external input
  3. Detect array-wrapped path segments
    Inspect all _.unset and _.omit calls to identify if any pass array-wrapped segments, such as _.unset(obj, ['key']) or _.omit(obj, ['prop1', 'prop2']) instead of plain string paths
    Affected if The vulnerable functions are called with array-wrapped path arguments like [key] rather than plain string keys
  4. Confirm input source is untrusted
    Trace the path argument back to its origin; check if it originates from HTTP request parameters, user uploads, database content, or other external sources
    Affected if The path argument passed to _.unset or _.omit comes from untrusted or user-controlled sources and includes array-wrapped segments

A user is affected if they have Lodash version 4.0.0 to below 4.17.23 AND their code uses _.unset or _.omit with array-wrapped path segments derived from untrusted input.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.17.23 or later
Fixed in 4.17.23
Interim mitigation

Upgrade lodash to version 4.18.0 or later to patch the vulnerability. There are no workarounds; applications using _.unset or _.omit with user-controlled paths are vulnerable.

Recommended fix High confidence

4.18.0

  1. Run `npm install lodash@^4.18.0` to upgrade to the patched version
  2. Verify the upgrade by running `npm list lodash` to confirm version 4.18.0 or higher is installed
  3. Run your test suite to ensure the upgrade does not break existing functionality
  4. If using a package-lock.json, consider deleting it and regenerating with `npm install` to ensure clean dependency resolution
Caveat Minor version bump may include minor changes; review Lodash 4.18.0 release notes for any impact

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Lodash Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,220
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-2950 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data