CVE-2026-25639 Axios affected by Denial of Service via __proto__ Key in mergeConfig
An attacker can cause a denial of service in Axios by providing a configuration object with a __proto__ key, crashing the application.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-25639?
CVE-2026-25639 is a high-severity denial of service vulnerability in axios, published on 9 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-25639?
4 open source packages ship an affected version, including axios. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
axios npm | All versions | 0.30.3 |
axios npm | All versions | 0.30.3 |
axios npm | From 1.0.0 | 1.13.5 |
axios npm | From 1.0.0 | 1.13.5 |
Products include Axios Axios.
How do I fix CVE-2026-25639?
Upgrade axios to a fixed version for your release line: 0.30.3 or 1.13.5.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-25639 being exploited?
There is no known exploitation of CVE-2026-25639 in the wild and no public exploit code.
Other vulnerabilities in axios
- CVE-2026-44494 Axios: Full Man-in-the-Middle via Prototype Pollution Gadget in `config.proxy`
- CVE-2026-44492 axios's shouldBypassProxy does not recognize IPv4-mapped IPv6 addresses, allowing NO_PROXY bypass (incomplete fix for CVE-2025-62718)
- CVE-2026-67320 axios before 0.33.0 Prototype Pollution via Node HTTP adapter
- CVE-2026-44487 Axios: Proxy-Authorization Credential Leak to Origin Server Across HTTP-to-HTTPS Redirect in Axios Node.js HTTP Adapter
- CVE-2025-27152 Possible SSRF and Credential Leakage via Absolute URL in axios Requests
Sources
Also known as CLEANSTART-2026-JD21137, CLEANSTART-2026-ZH04273, CLSA-2026-1776904633, CLSA-2026-1778028254, CLSA-2026-1792164130, DEBIAN-CVE-2026-25639 and 18 more.