Prototype Pollution in Axios

CVE-2026-42033

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.

Vulnerability class: Prototype Pollution

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.009 (58.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-42033: held from 0.008 to 0.009.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001

Affected products

  • Axios — versions >= 1.0.0, < 1.15.1, < 0.31.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42033?
CVE-2026-42033 is a high-severity vulnerability in Axios, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 7.4/10. Published 2026-04-24.
How severe is CVE-2026-42033?
High severity. CVSS v3 base score is 7.4 out of 10.