Axios up to 1.19.x Proxy Bypass shouldBypassProxy resource consumption

Summaryinfo

A vulnerability marked as problematic has been reported in Axios up to 1.19.x. The impacted element is the function shouldBypassProxy of the component Proxy Bypass. This manipulation causes resource consumption. This vulnerability is handled as CVE-2026-101906. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Axios up to 1.19.x. Affected by this vulnerability is the function shouldBypassProxy of the component Proxy Bypass. The manipulation with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. The summary by CVE is:

Axios is a promise-based HTTP client for the browser and Node.js. From 1.15.0 until 1.20.0, Axios shouldBypassProxy applies a quadratic trailing-dot regular expression to redirect hostnames. HTTP_PROXY or HTTPS_PROXY is configured, NO_PROXY or no_proxy is non-empty, redirects are followed, and a crafted redirect Location contains many dots followed by a non-dot character. Hostname.replace(/.+$/, '') backtracks quadratically while processing the crafted redirect hostname. Synchronous regular-expression processing can block the Node.js event loop and cause denial of service. This issue is fixed in version 1.20.0.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-101906 since 09/28/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 1.20.0 eliminates this vulnerability.

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Productinfo

Name

• Axios

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19

Website

• Product: https://github.com/axios/axios/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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