CVE-2026-42033: Axios: Prototype Pollution Gadgets - Response Tampering, Data Exfiltration, and Request Hijacking

Severity: high (CVSS 7.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-24 · updated 2026-09-10
Weakness: CWE-1321

Description

Axios is a promise based HTTP client for the browser and Node.js. Prior to 1.15.1 and 0.31.1, when Object.prototype has been polluted by any co-dependency with keys that axios reads without a hasOwnProperty guard, an attacker can (a) silently intercept and modify every JSON response before the application sees it, or (b) fully hijack the underlying HTTP transport, gaining access to request credentials, headers, and body. The precondition is prototype pollution from a separate source in the same process. This vulnerability is fixed in 1.15.1 and 0.31.1.

Affected products

axios: before 0.31.1; from 1.0.0 before 1.15.1 — fixed in 0.31.1, 1.15.1
Npm Axios: from 1.0.0 before 1.15.1; before 0.31.1 — fixed in 1.15.1, 0.31.1

How to fix

Upgrade to a fixed version: axios 0.31.1, 1.15.1; Npm Axios 1.15.1, 0.31.1. Check the vendor advisory for mitigations.

References

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