Description
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.
References5
Metrics
- CVSS 4.0
-
8.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 40 · as of 9 November 2026
- CWE
- CWE-400CWE-1333
Could this be exploited in your environment?
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