CVE-2026-101900

Published Sep 28, 2026 CWE-74 CWE-693 CWE-1321

Description

Axios is a promise-based HTTP client for the browser and Node.js. From 1.12.0 until 1.20.0, ResolveConfig reads inherited Symbol.toStringTag, append, and getHeaders properties while resolving FormData headers. A separate same-process prototype-pollution flaw supplies an array or non-plain class instance whose inherited properties make it appear FormData-like; plain objects are blocked. The inherited getHeaders function can return attacker-controlled headers that resolveConfig merges into a fetch adapter request. Attacker-controlled headers can alter authorization, cache, metadata-service, or application-specific request behavior. This issue is fixed in version 1.20.0.

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Weakness Type (CWE)

CWE-74 CWE-74
CWE-693 CWE-693
CWE-1321 CWE-1321

References

Frequently Asked Questions

What is CVE-2026-101900? +
Axios is a promise-based HTTP client for the browser and Node.js. From 1.12.0 until 1.20.0, ResolveConfig reads inherited Symbol.toStringTag, append, and getHeaders properties while resolving FormData headers. A separate same-process prototype-pollution flaw supplies an array or non-plain class instance whose inherited properties make it appear FormData-like; plain objects are blocked. The inherited getHeaders function can return attacker-controlled headers that resolveConfig merges into a fetch adapter request. Attacker-controlled headers can alter authorization, cache, metadata-service, or application-specific request behavior. This issue is fixed in version 1.20.0.
How do I check if I'm vulnerable to CVE-2026-101900? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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