CVE-2026-81887

Livewire is a full-stack framework for Laravel. From 3.0.0-beta.1 until 3.8.3 and 4.3.4, the dot-notated query-string parser in js/plugins/history/index.js, including fromQueryString() and insertDotNotatedValueIntoData(), accepts the __proto__, constructor, and prototype path segments and creates inherited objects. Client-side state handlers then access effects.html, effects.js, effects.xjs, and effects.scripts without Object.prototype.hasOwnProperty.call(), allowing inherited attacker-controlled state to be treated as trusted effects. An unauthenticated attacker can craft a URL that, when opened by a user, executes arbitrary JavaScript in the affected application's origin. Exploitation requires user interaction and does not bypass server-side authorization or grant privileges beyond the affected user. This issue is fixed in versions 3.8.3 and 4.3.4.

CVSS

No CVSS.

References

Link	Resource
https://github.com/livewire/livewire/commit/11ebe646f7e81dde2d714815da8b3019d058561e
https://github.com/livewire/livewire/pull/10467
https://github.com/livewire/livewire/releases/tag/v3.8.3
https://github.com/livewire/livewire/releases/tag/v4.3.4
https://github.com/livewire/livewire/security/advisories/GHSA-g3hc-697w-wm82

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-31 21:17

Updated : 2026-09-09 21:09

NVD link : CVE-2026-81887

Mitre link : CVE-2026-81887

CVE.ORG link : CVE-2026-81887

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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