Is CVE-2026-101903 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-101903 being exploited in the wild.

How severe is CVE-2026-101903?

High severity, with a CVSS score of 4, published 28 September 2026.

Which products and versions are affected?

Axios 1.16.1 through 1.19.x; axios (npm) >= 1.16.1, < 1.20.0, SEMVER:introduced=1.16.1,fixed=1.20.0.

Is there a fix for CVE-2026-101903?

Yes. axios (npm): upgrade to 1.20.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-101903 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-101903?

Check whether you run Axios or axios (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-101903: Axios regular expression denial of service in data URL parsing

Q: Is there a fix for CVE-2026-101903?

Yes. axios (npm): upgrade to 1.20.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-101903 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-101903?

Check whether you run Axios or axios (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-101903 · Severity: high · CVSS 4 · Published 2026-09-28

Axios is an HTTP client library used in web browsers and Node.js applications to fetch data from servers. Versions 1.16.1 through 1.20.0 contain a vulnerability in how they parse data URLs: if an attacker supplies a malformed data URL with many slash characters, the parser's regular expression engine gets stuck trying to match it, consuming all CPU and freezing the application. This can cause a denial of service where the application becomes unresponsive.

Technologies: Axios, axios (npm). Vendors: Axios, npm.

Quick answers

Is CVE-2026-101903 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-101903 being exploited in the wild.
How severe is CVE-2026-101903?: High severity, with a CVSS score of 4, published 28 September 2026.
Which products and versions are affected?: Axios 1.16.1 through 1.19.x; axios (npm) >= 1.16.1, < 1.20.0, SEMVER:introduced=1.16.1,fixed=1.20.0.
Is there a fix for CVE-2026-101903?: Yes. axios (npm): upgrade to 1.20.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-101903 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-101903?: Check whether you run Axios or axios (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

axios (npm): upgrade to 1.20.0 or later
```
npm install axios@1.20.0
```

Technical details

The vulnerability exists in the DATA_URL_PATTERN regular expression used by the fromDataURI function, which permits slash characters on both sides of the media-type separator and lacks a comma requirement. An attacker-controlled malformed data URL with excessive slashes and no comma triggers catastrophic backtracking in the JavaScript regex engine, causing synchronous blocking of the Node.js event loop. The issue is fixed in version 1.20.0 by hardening data URI validation to reject malformed URLs with extra slash separators.

Affected products

axios axios 1.16.1 through 1.19.x

Identifiers

CVE-2026-101903
GHSA-c29m-xwm3-cm6r

Timeline

2026-09-28: disclosed
2026-08-12: patched: Fixed in version 1.20.0

References

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