MediumGHSA-fvqr-27wr-82fmCVE-2018-3721

Prototype Pollution in lodash

Published 26 Jul 2018 · Updated 12 Aug 2025

Affected package

lodashnpm
Affected
<4.17.5
Fixed in
4.17.5
Update to the fixed version for your release line, for example:npm install lodash@4.17.5

Details

Versions of lodash before 4.17.5 are vulnerable to prototype pollution.

The vulnerable functions are 'defaultsDeep', 'merge', and 'mergeWith' which allow a malicious user to modify the prototype of Object via __proto__ causing the addition or modification of an existing property that will exist on all objects.

Recommendation

Update to version 4.17.5 or later.

Is GHSA-fvqr-27wr-82fm in any of your client repos?

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.