CVE-2025-3193: Algolia Algoliasearch-Helper

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

Versions of the package algoliasearch-helper from 2.0.0-rc1 and before 3.11.2 are vulnerable to Prototype Pollution in the _merge() function in merge.js, which allows constructor.prototype to be written even though doing so throws an error. In the "extreme edge-case" that the resulting error is caught, code injected into the user-supplied search parameter may be exeucted. This is related to but distinct from the issue reported in [CVE-2021-23433](https://security.snyk.io/vuln/SNYK-JS-ALGOLIASEARCHHELPER-1570421). **NOTE:** This vulnerability is not exploitable in the default configuration of InstantSearch since searchParameters are not modifiable by users.

Affected products

• Algolia Algoliasearch-Helper: from 2.0.0, before 3.11.2 (fixed in 3.11.2)

Published 2025-09-27. Last modified 2026-06-17.