{"id":"CVE-2026-81887","state":"PUBLISHED","title":"Livewire DOM-based cross-site scripting during client-side state handling","description":"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.","publishedAt":"2026-08-31T20:12:15.932Z","updatedAt":"2026-09-03T18:03:10.981Z","severity":{"score":5.1,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["livewire livewire"],"affected":[{"vendor":"livewire","product":"livewire","versions":[{"version":">= 3.0.0-beta.1, < 3.8.3","status":"affected"},{"version":">= 4.0.0-beta.1, < 4.3.4","status":"affected"}]}],"references":["https://github.com/livewire/livewire/security/advisories/GHSA-g3hc-697w-wm82","https://github.com/livewire/livewire/pull/10467","https://github.com/livewire/livewire/commit/11ebe646f7e81dde2d714815da8b3019d058561e","https://github.com/livewire/livewire/releases/tag/v3.8.3","https://github.com/livewire/livewire/releases/tag/v4.3.4"],"weaknesses":["CWE-79","CWE-1321"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/81xxx/CVE-2026-81887.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-81887","state":"PUBLISHED","datePublished":"2026-08-31T20:12:15.932Z","dateUpdated":"2026-09-03T18:03:10.981Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-08-27T17:48:42.123Z"},"containers":{"cna":{"title":"Livewire DOM-based cross-site scripting during client-side state handling","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"livewire","product":"livewire","versions":[{"version":">= 3.0.0-beta.1, < 3.8.3","status":"affected"},{"version":">= 4.0.0-beta.1, < 4.3.4","status":"affected"}]}],"references":[{"url":"https://github.com/livewire/livewire/security/advisories/GHSA-g3hc-697w-wm82","name":"https://github.com/livewire/livewire/security/advisories/GHSA-g3hc-697w-wm82","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/livewire/livewire/pull/10467","name":"https://github.com/livewire/livewire/pull/10467","tags":["x_refsource_MISC"]},{"url":"https://github.com/livewire/livewire/commit/11ebe646f7e81dde2d714815da8b3019d058561e","name":"https://github.com/livewire/livewire/commit/11ebe646f7e81dde2d714815da8b3019d058561e","tags":["x_refsource_MISC"]},{"url":"https://github.com/livewire/livewire/releases/tag/v3.8.3","name":"https://github.com/livewire/livewire/releases/tag/v3.8.3","tags":["x_refsource_MISC"]},{"url":"https://github.com/livewire/livewire/releases/tag/v4.3.4","name":"https://github.com/livewire/livewire/releases/tag/v4.3.4","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"ACTIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","baseScore":5.1,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1321","lang":"en","description":"CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-31T20:12:15.932Z"},"source":{"advisory":"GHSA-g3hc-697w-wm82","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-03T18:03:04.888165Z","id":"CVE-2026-81887","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-03T18:03:10.981Z"}}]}}}