CVE-2026-101908

Axios: Prototype pollution gadget in fetch adapter can alter outbound requests

Axios is a promise-based HTTP client for the browser and Node.js. From 1.7.0 until 1.20.0, the fetch adapter constructs a Request with sanitized resolvedOptions but then calls fetch with the original fetchOptions. A separate same-process prototype-pollution flaw populates Object.prototype.headers so fetchOptions.headers resolves through inheritance. The inherited fetchOptions.headers value overrides the sanitized Request headers through the second argument to fetch after Request construction. Attacker-controlled request headers can alter authorization, caching, metadata-service access, or application-specific behavior. This issue is fixed in version 1.20.0.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

Axios

Products

Axios

CVE-2026-101900

Axios: Fetch Adapter Header Injection via Inherited FormData getHeaders

Axios is a promise-based HTTP client for the browser and Node.js. From 1.12.0 until 1.20.0, ResolveConfig reads inherited Symbol.toStringTag, append, and getHeaders properties while resolving FormData headers. A separate same-process prototype-pollution flaw supplies an array or non-plain class instance whose inherited properties make it appear FormData-like; plain objects are blocked. The inherited getHeaders function can return attacker-controlled headers that resolveConfig merges into a fetch adapter request. Attacker-controlled headers can alter authorization, cache, metadata-service, or application-specific request behavior. This issue is fixed in version 1.20.0.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

Axios

Products

Axios

CVE-2026-101904

Axios: Header Injection via Inherited headers After Minimal Interceptor

Axios is a promise-based HTTP client for the browser and Node.js. From 1.0.0 until 1.20.0, the dispatchRequest function normalizes inherited Object.prototype.headers from a replacement request configuration. A separate same-process prototype-pollution flaw sets Object.prototype.headers, and trusted request interceptors return a new ordinary configuration without an own headers property. After the interceptor chain, dispatchRequest resolves the inherited headers during normalization. Downstream request processing can observe attacker-controlled headers, including authorization-related values. This issue is fixed in version 1.20.0.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

Axios

Products

Axios

CVE-2026-97724

Prototype Pollution Leading to Remote Denial of Service via React Native Worklets

A prototype pollution vulnerability in Software Mansion React Native Worklets before 0.12.2 allows an attacker-controlled object containing a __proto__ property to modify the prototype of an object created during serialization in clonePlainJSObject in packages/react-native-worklets/src/memory/serializable.native.ts. When affected data is subsequently processed by React Native Worklets, the malformed serialized object can cause the React Native application to crash. This can result in a remotely triggered denial of service in applications that pass attacker-controlled data through the affected serialization path. In applications where the attacker-controlled data is persisted, the denial of service may persist across application restarts or repeated attempts to access the affected content.

CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed

Vendors

Swmansion

Products

React Native Reanimated

CVE-2026-9101

Prototype pollution in csv parsing

Prototype pollution in csv parsing logic during import can lead to untrusted file paths (but not arguments) entering shell.openExternal after specific user behavior leading to "1-click" command execution.

CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed

Vendors

Mongodb

Products

Compass

CVE-2026-97151

Prototype Pollution in mammoth.js via Malicious DOCX

mammoth (aka mammoth.js) before 1.12.2 is vulnerable to prototype pollution when reading the styles defined in a document. Converting a crafted .docx file allows an attacker to add arbitrary properties to Object.prototype. In 1.11.0 through 1.12.1, applications that convert further documents in the same process and return the converted HTML can also disclose the contents of local server files (to the party supplying the documents) by setting externalFileAccess to true.

CVSS 4.0 · 8.4 High EPSS < 1% KEV · Not listed

Vendors

Mwilliamson

Products

Mammoth.js

CVE-2026-61834

scim-patch: Mutation of Inherited Built-in Method Objects

scim-patch is a library for applying SCIM patch operations. Prior to 0.9.2, navigate() reads inherited properties and assign() uses prototype-chain membership checks while resolving attacker-controlled SCIM PATCH paths. A path or one of the dotted value keys beginning with an inherited property such as toString can therefore traverse into a shared built-in function object and add attacker-controlled properties, causing process-global mutation that may affect application logic reading inherited-method properties. This issue is fixed in version 0.9.2.

CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed

Vendors

Thomaspoignant

Products

Scim-patch

CVE-2026-92781

Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via builder.userAttributes

Builder.io Gen2 SDKs through versions 5.2.11 and 0.25.13 contain a prototype pollution vulnerability in the unflatten helper that processes builder.userAttributes query parameters without prototype guards. Attackers can craft preview links with __proto__ or prototype segments to pollute Object.prototype in a visitor's browser when the SDK processes the malicious URL.

CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed

Vendors

Builderio

Products

Sdk-angular Sdk-qwik Sdk-react and 4 more

CVE-2026-69200

node-opcua: Prototype Pollution via internal `fieldsToJson()` implementation (Related to CVE-2024-57086)

node-opcua is an OPC UA implementation for TypeScript and Node.js. Prior to node-opcua-client 2.145.0, the internal fieldsToJson method in packages/node-opcua-client/source/alarms_and_conditions/client_alarm.ts directly assigns unsanitized field names and allows a __proto__.pollutedKey path to modify Object.prototype. Successful exploitation requires an application to expose attacker-controlled event fields to fieldsToJson and may cause denial of service or application logic corruption. This vulnerability is fixed in 2.145.0.

CVSS 3.1 · 3.7 Low EPSS < 1% KEV · Not listed

Vendors

Node-opcua Project

Products

Node-opcua

CVE-2026-73654

Trigger.dev: Prototype pollution via run metadata operations → process-wide cross-tenant DoS

Trigger.dev is a platform for building and deploying fully managed AI agents and workflows. From 3.3.8 until 4.5.6, the PUT /api/v1/runs/:runId/metadata endpoint passes attacker-controlled operation.key values to new JSONHeroPath(operation.key).set(newMetadata, value) in packages/core/src/v3/runMetadata/operations.ts without rejecting dangerous constructor and prototype path segments. A caller with a normal environment API key can pollute Object.prototype in the shared webapp process, corrupting Prisma queries and Prometheus labels, breaking other tenants' worker authentication, and causing a process-wide denial of service. This issue is fixed in version 4.5.6.

CVSS 3.1 · 8.5 High EPSS < 1% KEV · Not listed

Vendors

Triggerdotdev

Products

Trigger.dev

CVE-2026-92779

Builder.io Gen2 SDKs through 5.2.11 Prototype Pollution via Bindings

Builder.io Gen2 SDKs through versions 5.2.11 and 0.25.13 contain a prototype pollution vulnerability in the deep-set helper function that processes content block bindings without validation. Attackers can craft content blocks with binding keys containing __proto__, prototype, or constructor paths to pollute Object.prototype during rendering, affecting all subsequent objects created in the process including other tenants' renders.

CVSS 4.0 · 7.2 High EPSS < 1% KEV · Not listed

Vendors

Builderio

Products

Sdk-angular Sdk-qwik Sdk-react and 4 more

CVE-2026-72769

n8n before 1.123.67 Prototype Pollution via VM Expression Engine

n8n before 1.123.67, 2.31.5, and 2.32.1 contains a prototype pollution vulnerability in the VM expression engine. An authenticated user able to create or edit a workflow expression can abuse the engine's array-element access to obtain a reference to a host built-in and pollute its prototype in the main n8n process (a sandbox escape), leading to a denial of service. Both self-hosted and cloud instances running the VM expression engine are affected.

CVSS 4.0 · 6.1 Medium EPSS < 1% KEV · Not listed

Vendors

N8n

Products

N8n

CVE-2026-61534

Yayson: Prototype pollution in the Store/LegacyStore deserialization

Yayson is a library for serializing and reading JSON API data in JavaScript. Prior to 4.3.0, Store and LegacyStore use attacker-controlled JSON:API type, id, and relationship names as keys in plain-object lookup tables in src/yayson/store.ts and src/yayson/legacy-store.ts. A document whose type is __proto__ causes model-cache writes to modify Object.prototype, with the attacker controlling the polluted property name through id and its value through attributes. The malicious type can also be supplied by an included resource, and LegacyStore is reachable when a configured types mapping resolves to __proto__. Unsafe relationship names including __proto__, constructor, and prototype provide additional document-derived member paths. The resulting process-wide prototype pollution can cause denial of service and logic corruption; authorization bypass or code execution depends on suitable gadgets in the consuming application. This issue is fixed in version 4.3.0.

CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed

Vendors

Confetti

Products

Yayson

CVE-2026-55451

gettext-converter: Prototype pollution in js2i18next() via crafted translation keys

gettext-converter provides gettext resource conversion utilities for JavaScript. Prior to 1.3.3, js2i18next() in lib/js2i18next.js splits nested translation keys using options.keyseparator, whose default value consists of two number signs, and uses each segment as a dynamic object key without rejecting __proto__, constructor, or prototype. When an application converts untrusted PO or i18next translation data, a __proto__ segment resolves Object.prototype as the nested write target and Object.assign writes attacker-controlled translated properties onto the process-wide prototype. The resulting prototype pollution can cause denial of service and may enable application-dependent follow-on attacks. This issue is fixed in version 1.3.3.

CVSS 4.0 · 8.3 High EPSS < 1% KEV · Not listed

Vendors

Locize

Products

Gettext-converter

CVE-2026-55091

flat-to-nested: Prototype pollution in flat-to-nested convert() via __proto__ parent/id key

flat-to-nested converts a hierarchy from a flat representation to a nested representation. Prior to 1.1.2, FlatToNested.prototype.convert in index.js uses attacker-influenced id and parent record fields directly as keys in the plain temp and pendingChildOf objects. When parent or id is __proto__, temp[parent] can resolve to Object.prototype, and initPush() can write attacker-controlled data to the global children prototype property while existing prototype methods remain intact. Any application that passes attacker-influenced flat records to convert() can therefore expose unrelated objects to polluted inherited state, causing application-logic corruption or denial of service and potentially enabling greater impact when a downstream prototype-pollution gadget is present. The constructor and prototype strings are also unsafe inherited-key values in the same lookup design. This issue is fixed in version 1.1.2.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Joaonuno

Products

Flat-to-nested-js

CVE-2026-90771

joi before 17.13.8 and 18.2.9 Prototype Pollution via messages

joi before versions 17.13.8 and 18.2.9 contains a prototype pollution vulnerability in the messages compilation function that accepts __proto__ as an error code. Attackers can supply __proto__ keys in custom messages to replace the returned object's prototype, breaking downstream code relying on Object.prototype methods.

CVSS 4.0 · 6.3 Medium EPSS < 1% KEV · Not listed

Vendors

Hapijs

Products

Joi

CVE-2026-85625

sift 17.1.3 Prototype Pollution Remote Code Execution via $where

sift (sift.js) 17.1.3 enumerates query keys with for...in, which walks the object prototype chain, and dispatches any matched operator key including $where. The $where operation compiles a string value into a function using new Function unless CSP_ENABLED is set (not set by default). As a result, if a prototype-pollution primitive elsewhere in the process sets Object.prototype.$where to a malicious string, even benign filter calls such as sift({}) execute arbitrary JavaScript. Additionally, passing an untrusted query object containing a string $where directly to sift results in code execution under the default configuration.

CVSS 4.0 · 9.2 Critical EPSS < 1% KEV · Not listed

Vendors

Crcn

Products

Sift.js

CVE-2026-89011

isomorphic-git < 1.42.0 Prototype Pollution via getRemoteInfo

isomorphic-git before 1.42.0 contains a prototype pollution vulnerability in the getRemoteInfo function that allows a malicious Git server operator to pollute Object.prototype by advertising crafted ref names containing '__proto__' path segments during ref negotiation. Attackers controlling a Git server can advertise a specially crafted ref such as '__proto__/corsProxy' to reroute all subsequent network operations through an attacker-controlled proxy, causing isomorphic-git to invoke the victim's onAuth callback and transmit credentials to the attacker when the victim calls getRemoteInfo with an attacker-supplied URL.

CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed

Vendors

Isomorphic-git

Products

Isomorphic-git

CVE-2026-86078

n8n: Prototype Pollution via Workflow Structure Summary Can Lead to Denial of Service

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.2, the Instance AI workflow summary used node names and connection keys from stored workflows as ordinary object keys. A workflow submitted through the REST API could contain __proto__ or constructor, causing nested writes to reach Object.prototype in the main n8n process and disrupt later requests. The affected function is summarizeWorkflowStructure in packages/@n8n/instance-ai/src/tools/workflows/summarize-workflow.ts. This issue is fixed in versions 2.37.7 and 2.38.2.

CVSS 4.0 · 6 Medium EPSS < 1% KEV · Not listed

Vendors

N8n

Products

N8n

CVE-2026-44495

Axios: Credential Theft and Response Hijacking via Prototype Pollution Gadget in Config Merge

Axios is a promise based HTTP client for the browser and Node.js. From 0.19.0 to before 0.31.1 and 1.15.2, Axios contains prototype-pollution gadgets in request config processing. If another vulnerability in the same JavaScript process has already polluted Object.prototype.transformResponse, affected Axios versions may treat that inherited value as request configuration or as an option validator. Axios does not itself create the prototype pollution. Exploitability requires a separate prototype-pollution vulnerability or equivalent attacker control over Object.prototype before Axios creates a request. This vulnerability is fixed in 0.31.1 and 1.15.2.

CVSS 3.1 · 7 High EPSS < 1% KEV · Not listed

Vendors

Axios Redhat

Products

Axios Advanced Cluster Management For Kubernetes Advanced Cluster Security and 9 more