Vulnerability · Published Oct 13, 2026 · Assigned by GitHub_M

CVE-2026-101899Axios: CIDR-form NO_PROXY entries are ignored, causing proxy exclusion bypass for internal IP ranges

Medium 6.9

In plain English

A medium-severity security flaw in axios from axios. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.5%top 56.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Axios is a promise-based HTTP client for the browser and Node.js. From 1.15.0 until 1.20.0, Axios shouldBypassProxy treats the NO_PROXY CIDR form as a textual hostname suffix instead of evaluating the network range. A request targets an address covered by a CIDR entry in NO_PROXY while a proxy is configured. The CIDR bypass rule is not matched, so the request is sent through the configured proxy. For plaintext HTTP, the proxy can observe and modify URLs, headers, and bodies; for HTTPS, it can observe connection metadata and CONNECT requests. This issue is fixed in version 1.20.0.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:14node-axios1.20.0-1DEBIAN-CVE-2026-101899
Ubuntu:26.10node-axiosno fix listedUBUNTU-CVE-2026-101899
npmaxios1.20.0GHSA-44g4-m2mj-wpvx

Affected products (as reported)

VendorProductVersions
axios axios >= 1.15.0, < 1.20.0

Weakness: CWE-693 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N

References