Componentpedia / Listings / axios / 1.15.1

Axios shouldBypassProxy() normalizes hostnames with hostname.replace(/.+$/, ''). For a hostname shaped as many dots followed by a non-dot, the anchored regex can perform quadratic backtracking. Because axios re-evaluates proxy bypass rules for redirected requests, a malicious server can trigger this synchronous work through a crafted redirect Location.

Axios request interceptors may return a replacement config object. If an interceptor returns a plain object without an own headers property, dispatchRequest() later evaluates config.headers and can resolve an inherited Object.prototype.headers value. In a process where another vulnerability has polluted Object.prototype.headers, axios can send attacker-controlled headers.

axios versions 0.28.0 and later contain uncontrolled recursion in formDataToJSON when processing FormData field names with deeply nested bracket segments. Attackers can supply FormData with field names containing thousands of nested brackets to exhaust the JavaScript call stack and trigger RangeError, causing request failure or process termination in applications that do not handle the exception.

Axios is a promise based HTTP client for the browser and Node.js. From 1.0.0 to before 1.16.0, the Axios library is vulnerable to a Prototype Pollution "Gadget" attack that allows any Object.prototype pollution in the application's dependency tree to be escalated into a full Man-in-the-Middle (MITM) attack — intercepting, reading, and modifying all HTTP traffic including authentication credentials. The HTTP adapter at lib/adapters/http.js:670 reads config.proxy via standard property access, which traverses the prototype chain. Because proxy is not present in Axios defaults, the merged config object has no own proxy property, making it trivially injectable via prototype pollution. Once injected, setProxy() routes all HTTP requests through the attacker's proxy server. This vulnerability is fixed in 1.16.0.

Axios is a promise based HTTP client for the browser and Node.js. Axios versions 1.7.0 through 1.15.x did not enforce configured request and response size limits when requests were sent with the fetch adapter. Applications that selected adapter: 'fetch', or ran in environments where axios resolved to the fetch adapter, could receive or send bodies larger than maxContentLength or maxBodyLength despite those limits being explicitly configured. This can cause resource exhaustion in server-side usage when a malicious or compromised server returns an oversized response, when an attacker can supply a large data: URL, or when an application forwards attacker-controlled request bodies through axios while relying on maxBodyLength as a boundary. This vulnerability is fixed in 0.32.0 and 1.16.0.

Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, Axios’ Node.js HTTP adapter can leak proxy credentials to a redirect target in affected versions. When a request is sent through an authenticated proxy, Axios may add a Proxy-Authorization header. If Axios then follows a redirect and the redirected request is no longer sent through that proxy, the stale Proxy-Authorization header can remain on the redirected request and be sent to the redirect target. This affects Node.js's use of Axios with automatic redirects enabled and an authenticated proxy configuration. Browser adapters are not affected. This vulnerability is fixed in 0.32.0 and 1.16.0.

axios is vulnerable to read-side prototype-pollution gadgets that can alter request construction when Object.prototype has already been polluted by a separate vulnerability or dependency. In the bodyless method aliases (axios.get(), axios.delete(), axios.head(), axios.options()), inherited data is read via (config || {}).data before config normalization, causing an attacker-controlled body to be sent on requests that did not set one. Additional low-level paths, only reachable when calling exported adapters/helpers (e.g. lib/adapters/http.js, unsafe/helpers/resolveConfig.js) directly with plain configs and no own proxy or paramsSerializer, can inherit polluted proxy values (routing requests through an attacker-controlled proxy) or paramsSerializer values (attacker-controlled URL serialization). These low-level gadgets do not reproduce through normal high-level axios calls on 1.15.2+. The issue is fixed in axios 1.18.0 and 0.33.0.

Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, Axios’s Node.js HTTP adapter may forward a Proxy-Authorization header to a redirected origin during specific proxy-to-direct redirect flows. This affects Node.js usage, where an initial HTTP request is sent through an authenticated HTTP proxy, redirects are followed, and the redirected URL is no longer proxied. Under affected redirect shapes, the final origin can receive the proxy credential that was intended only for the outbound proxy. This vulnerability is fixed in 0.32.0 and 1.16.0.

Axios supports proxy environment variables and evaluates NO_PROXY exclusions in the Node.js adapter. CIDR-form NO_PROXY entries such as 127.0.0.0/8, 10.0.0.0/8, or 169.254.169.254/32 are not interpreted as IP ranges. As a result, a request to an IP address inside a configured CIDR exclusion can still be sent through the configured proxy.

axios 1.15.2 exposes two read-side prototype-pollution gadgets. When Object.prototype is polluted by an upstream dependency in the same process (e.g. lodash _.merge / CVE-2018-16487), axios silently picks up the polluted values:

axios versions from 0.28.0 before 0.33.0 and from 1.0.0 before 1.18.0 contain uncontrolled recursion in formDataToJSON (exposed as axios.formToJSON() and used internally when serializing FormData with Content-Type: application/json). When an application passes attacker-controlled FormData field names, a field name with thousands of nested bracket-delimited segments causes unbounded recursion in buildPath(), exhausting the JavaScript call stack (RangeError: Maximum call stack size exceeded) and causing denial of service for that request, or process termination in applications without appropriate error handling.

Axios versions with Node.js HTTP/2 support can terminate the caller’s process when a ClientHttp2Session emits an error event that is not handled by axios.

Axios is a promise based HTTP client for the browser and Node.js. Axios versions before 0.32.0 on the 0.x line and before 1.16.0 on the 1.x line build a regular expression from the configured XSRF cookie name without escaping regex metacharacters. In standard browser environments, an attacker who can influence the cookie name passed to axios can cause expensive regex backtracking while axios reads document.cookie. The practical impact is client-side availability degradation, such as freezing the affected browser tab while axios prepares a request. The issue does not affect ordinary Node.js HTTP adapter usage, React Native, or web workers, where axios does not read document.cookie. This vulnerability is fixed in 0.32.0 and 1.16.0.

Axios for Node.js does not apply configured DNS lookup or proxy controls when a request uses httpVersion: 2. The HTTP/1 adapter path wraps and forwards config.lookup, builds normal request options, and applies proxy routing through setProxy(). The HTTP/2 path builds a session with http2.connect() using only options.http2Options, which drops the top-level lookup, agent, and proxy state.

Axios form serialization reads visitor, maxDepth, dots, indexes, metaTokens, and Blob from an internal options object without own-property guards. When Object.prototype has been polluted elsewhere in the same process, those inherited values can change how axios serializes multipart and URL-encoded request bodies.

axios versions 0.31.0 before 0.33.0 and 1.15.0 before 1.18.0 fail to recognize 0.0.0.0 as a loopback address in shouldBypassProxy.js, allowing requests to 0.0.0.0 to bypass NO_PROXY rules. Attackers can supply 0.0.0.0 URLs to route requests through configured proxies, potentially exposing local services when the proxy can reach the destination.

axios before 0.33.0 (and 1.x before 1.18.0) can consume inherited properties from nested request option objects when the JavaScript process's Object.prototype has already been polluted by another component. While the top-level merged config uses a null prototype, nested plain objects such as auth and paramsSerializer are cloned into ordinary objects and read without own-property checks. When an application passes placeholder nested objects such as auth: {} or paramsSerializer: {}, inherited username/password values can cause silent injection of an Authorization: Basic header, and inherited encode/serialize values can alter query-string serialization (full serializer replacement requires a function-valued pollution primitive). This is exploitable only in the presence of pre-existing prototype pollution.

Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, Axios does not normalise IPv4-mapped IPv6 addresses. When NO_PROXY lists an IPv4 address such as 127.0.0.1 or 169.254.169.254, a request URL using the IPv4-mapped IPv6 form (::ffff:7f00:1, ::ffff:a9fe:a9fe) still routes through the configured proxy. Node.js resolves these addresses to the underlying IPv4 host, so the request reaches the internal service via the proxy rather than being blocked. This vulnerability is fixed in 0.32.0 and 1.16.0.

Axios is a promise based HTTP client for the browser and Node.js. From version 1.0.0 to before version 1.15.2, fFive config properties (auth, baseURL, socketPath, beforeRedirect, and insecureHTTPParser) in the HTTP adapter are read via direct property access without hasOwnProperty guards, making them exploitable as prototype pollution gadgets. When Object.prototype is polluted by another dependency in the same process, axios silently picks up these polluted values on every outbound HTTP request. This issue has been patched in version 1.15.2.

Axios fetch adapter requests can be altered by inherited properties on fetchOptions. The adapter resolves method, headers, body, signal, and credentials into resolvedOptions, creates a Request, and then calls fetch(request, fetchOptions) instead of fetch(request, resolvedOptions). In runtimes such as Node's undici-backed fetch, inherited fetchOptions.headers can override the headers already placed on the Request.

axios versions 0.31.1 before 0.33.0 and 1.15.1 before 1.18.0 contain an incomplete depth-limit bypass in toFormData.js when serializing objects with top-level keys ending in '{}'. Attackers who control object keys and nested values passed to axios form or parameter serialization can trigger a RangeError from JSON.stringify, causing denial of service in the affected request path.

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.

axios versions 1.7.0 before 1.18.0 fail to enforce maxBodyLength for WHATWG ReadableStream request bodies in the fetch adapter when Content-Length cannot be determined. Attackers can supply unknown-length stream data to bypass upload size limits and cause uncontrolled network egress or resource exhaustion.

axios versions >=1.13.0 (Node.js HTTP adapter) fail to enforce the configured maxBodyLength limit on streamed request bodies when requests are sent with httpVersion: 2. Because Node's HTTP/2 request API does not honor the maxBodyLength option and axios's byte-counting stream wrapper is gated on maxRedirects === 0, an attacker who controls a stream passed to axios can cause the application to transmit outbound data exceeding the configured finite maxBodyLength. Impact is limited to resource consumption and policy bypass (excess egress, upstream quota consumption, limited availability); it does not enable code execution, credential disclosure, or request-destination control. Calls using the default maxBodyLength: -1 and browser adapters are not affected.

Axios contains a guard in the Node HTTP adapter to avoid using an inherited Object.prototype.getHeaders as a FormData header source. The fetch adapter calls the shared resolveConfig() helper before dispatch, and that helper lacks the same guard. If another vulnerability pollutes Object.prototype with FormData-like properties and getHeaders(), the fetch adapter can merge attacker-controlled headers into the outbound request.

Axios default-instance requests that omit an explicit method can read an inherited method value from Object.prototype. If another vulnerability in the same process pollutes Object.prototype.method, calls such as axios.request({ url }) and axios({ url }) can send a state-changing HTTP method instead of the expected default GET.

Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, axios exposes two read-side prototype-pollution gadgets. When Object.prototype is polluted by an upstream dependency in the same process (e.g. lodash _.merge / CVE-2018-16487), axios silently picks up the polluted values. (1) lib/utils.js line 406 builds merge()'s accumulator as result = {}, so result[targetKey] (line 414) walks Object.prototype and the polluted bucket's own keys are copied into the merged headers and ride out on the wire. (2) lib/core/mergeConfig.js line 26 builds the hasOwnProperty descriptor as a plain-object literal. Object.defineProperty reads descriptor.get/descriptor.set via the prototype chain, so a polluted Object.prototype.get or Object.prototype.set makes the call throw TypeError synchronously on every axios request. This vulnerability is fixed in 0.32.0 and 1.16.0.