CWE-1321: Prototype Pollution
The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.
254 tracked CVEs are classified under this weakness.
Highest-risk vulnerabilities
- CVE-2026-34621 — Acrobat Reader | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (CWE-1321)
- CVE-2026-32621 — Apollo Federation has prototype pollution via incomplete key sanitization
- CVE-2025-25015 — Kibana arbitrary code execution via prototype pollution
- CVE-2026-33994 — Locutus Prototype Pollution due to incomplete fix for CVE-2026-25521
- CVE-2026-21854 — Tarkov Data Manager Authentication Bypass vulnerability
- CVE-2024-27307 — JSONata expression can pollute the "Object" prototype
- CVE-2026-33696 — n8n Vulnerable to Prototype Pollution in XML & GSuiteAdmin node parameters lead to RCE
- CVE-2026-26021 — Prototype pollution in set-in
- CVE-2026-25047 — deepHas vulnerable to Prototype Pollution via constructor.prototype
- CVE-2025-62410 — --disallow-code-generation-from-strings is not sufficient for isolating untrusted JavaScript in happy-dom
- CVE-2024-56059 — WordPress Partners plugin <= 0.2.0 - PHP Object Injection vulnerability
- CVE-2026-28794 — oRPC: Prototype Pollution in `@orpc/client` via `StandardRPCJsonSerializer` Deserialization
- CVE-2026-25150 — Prototype Pollution via FormData Processing in Qwik City
- CVE-2025-13158 — apidoc-core - prototype pollution in api_group.js, api_param_title.js, api_use.js, and api_permission.js worker
- CVE-2026-25881 — @nyariv/sandboxjs has host prototype pollution from sandbox via array intermediary (sandbox escape)
- CVE-2025-66456 — Elysia vulnerable to prototype pollution with multiple standalone schema validation
- CVE-2025-25014 — Kibana arbitrary code execution via prototype pollution
- CVE-2024-48910 — DOMPurify vulnerable to tampering by prototype polution
- CVE-2025-27597 — Vue I18n Prototype Pollution in `handleFlatJson`
- CVE-2026-30939 — Parse Server has Denial of Service (DoS) and Cloud Function Dispatch Bypass via Prototype Chain Resolution
Recently published
- CVE-2026-86078 — n8n: Prototype Pollution via Workflow Structure Summary Can Lead to Denial of Service
- CVE-2026-81994 — Acrobat Reader | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (CWE-1321)
- CVE-2026-85625 — sift 17.1.3 Prototype Pollution Remote Code Execution via $where
- CVE-2026-63376 — toml-node: Prototype Pollution Leads to `Object.prototype` Corruption via `__proto__` Key-Path Desynchronization
- CVE-2026-85063 — node-csv: Prototype replacement still reachable via columns path
- CVE-2026-82404 — TOON: Prototype pollution when decoding untrusted TOON input
- CVE-2026-84368 — joi: Prototype pollution via a `__proto__` language key in custom messages
- CVE-2026-84367 — joi: object().rename() with a template target can set the validated object's prototype
- CVE-2026-81887 — Livewire DOM-based cross-site scripting during client-side state handling
- CVE-2026-82257 — SvelteKit before 2.69.1 Prototype Pollution via File Input
- CVE-2026-78654 — cleverbrush framework/deep deepExtend.ts deepExtend prototype pollution
- CVE-2026-78181 — ractivejs ractive Keypath Ractive#set prototype pollution
- CVE-2026-78180 — alibaba-fusion next deepMerge index.tsx ConfigProvider.getContextProps prototype pollution
- CVE-2026-78179 — rexrainbow phaser3-rex-notes BehaviorTree Blackboard Data SetValue.js SetValue prototype pollution
- CVE-2026-78178 — jQWidgets jqx-all.js jqxBaseFramework.extend prototype pollution
- CVE-2026-78207 — exceljs through 4.4.0 Prototype Pollution via deepMerge Reached From Note Serialization
- CVE-2026-18420 — RCE via Prototype Pollution in OpenSearch Dashboards
- CVE-2026-77083 — n8n before 1.123.69 Code Node Sandbox Escape via Function.prototype Pollution
- CVE-2026-23929 — Prototype pollution leading to stored XSS
- CVE-2026-71553 — ApostropheCMS: 2nd-order prototype pollution via PATCH leading to single-request persistent DoS