CVE-2026-101908: Prototype Pollution

Description

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.

Is your site exposed to CVE-2026-101908?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0041

Probability of exploitation

0.34%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-1321 CWE-1321

References

Other References

https://github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a https://github.com/axios/axios/pull/11141 https://github.com/axios/axios/releases/tag/v1.20.0 https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8 https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8

Frequently Asked Questions

What is CVE-2026-101908? +

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.

How do I check if I'm vulnerable to CVE-2026-101908? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-104852

GraphQL Tools provides utilities for building, stitching, and mocking GraphQL schemas. Prior to 12.0.1, the GraphQL Tools utils package's mergeDeep …

CVE-2026-104849

Tinypool is a minimal Node.js worker thread pool implementation. Prior to 2.1.2, Tinypool reads filename from a caller-supplied options object …

CVE-2025-27597

Vue I18n is the internationalization plugin for Vue.js. @intlify/message-resolver and @intlify/vue-i18n-core are vulnerable to Prototype Pollution through the entry function: …

CVE-2025-32014

estree-util-value-to-estree converts a JavaScript value to an ESTree expression. When generating an ESTree from a value with a property named …

CVE-2025-48054

Radashi is a TypeScript utility toolkit. Prior to version 12.5.1, the set function within the Radashi library is vulnerable to …

CVE-2025-8101

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') vulnerability in Linkify (linkifyjs) allows XSS Targeting HTML Attributes and Manipulating …

CVE-2026-101908