CVE-2026-101904 Axios: Header Injection via Inherited headers After Minimal Interceptor
Attackers can inject malicious headers into HTTP requests via prototype pollution, potentially bypassing security controls or modifying request data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-101904?
CVE-2026-101904 is a medium-severity vulnerability in axios, published on 28 Sep 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. From 1.0.0 until 1.20.0, the dispatchRequest function normalizes inherited Object.prototype.headers from a replacement request configuration. A separate same-process prototype-pollution flaw sets Object.prototype.headers, and trusted request interceptors return a new ordinary configuration without an own headers property. After the interceptor chain, dispatchRequest resolves the inherited headers during normalization. Downstream request processing can observe attacker-controlled headers, including authorization-related values. This issue is fixed in version 1.20.0.
Which versions are affected by CVE-2026-101904?
2 open source packages ship an affected version, including axios.
| Package | Affected | Fixed in |
|---|---|---|
axios npm | From 1.0.0 | 1.20.0 |
axios npm | From 1.0.0 | 1.20.0 |
How do I fix CVE-2026-101904?
Upgrade axios to 1.20.0 or later.
Is CVE-2026-101904 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-101904 exists.
Sources
Also known as AZL-105257, CLEANSTART-2026-LD08351, CLEANSTART-2026-OV09426, CLEANSTART-2026-XI51543, DEBIAN-CVE-2026-101904, ECHO-1fea-28a8-5aef and 20 more.