CVE-2026-25639: Axios affected by Denial of Service via __proto__ Key in mergeConfig

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 28 Oct 2026. It cites 1 public report, the first from 28 Oct 2026.

• levelblue.com

How likely is exploitation in the next 30 days?

2.8%

Up from 2% on 22 Oct 2026.

EPSS score, percentile 86.4 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

7.5 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• >= 1.0.0, < 1.13.5
• < 0.30.3

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

Axios affected by Denial of Service via __proto__ Key in mergeConfig

Axios is a promise based HTTP client for the browser and Node.js. Prior to versions 0.30.3 and 1.13.5, the mergeConfig function in axios crashes with a TypeError when processing configuration objects containing __proto__ as an own property. An attacker can trigger this by providing a malicious configuration object created via JSON.parse(), causing complete denial of service. This vulnerability is fixed in versions 0.30.3 and 1.13.5.

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Source: CVE List, as of 30 Oct 2026. About the data.

Timeline