CVE-2026-42043
Published: 24 April 2026
Summary
CVE-2026-42043 is a high-severity Permissive List of Allowed Inputs (CWE-183) vulnerability in Axios Axios. Its CVSS base score is 7.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 47.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).
Deeper analysis
CVE-2026-42043 is a vulnerability in Axios, a promise-based HTTP client used in browsers and Node.js environments. It affects versions prior to 1.15.1 and 0.31.1, stemming from an incomplete fix for CVE-2025-62718. The flaw allows an attacker who can influence the target URL of an Axios request to bypass NO_PROXY protection by using any address in the 127.0.0.0/8 range except 127.0.0.1. The vulnerability is rated 7.2 on the CVSS v3.1 scale (AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N) and is associated with CWE-183, CWE-441, and CWE-918.
An attacker with the ability to control or influence the target URL in an Axios request—such as through user-supplied input or manipulated parameters—can exploit this remotely over the network with low complexity and no privileges or user interaction required. Successful exploitation bypasses NO_PROXY protections, potentially enabling server-side request forgery (SSRF) or similar attacks by directing requests to loopback addresses that evade proxy bypass rules, resulting in limited confidentiality and integrity impacts with a changed scope.
The GitHub security advisory (GHSA-pmwg-cvhr-8vh7) confirms the issue is fixed in Axios versions 1.15.1 and 0.31.1. Security practitioners should update to these patched versions immediately and review applications using Axios for URL validation to prevent influence by untrusted inputs.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-25608
Vulnerability details
Axios is a promise based HTTP client for the browser and Node.js. Prior to 1.15.1 and 0.31.1, an attacker who can influence the target URL of an Axios request can use any address in the 127.0.0.0/8 range (other than 127.0.0.1)…
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to completely bypass the NO_PROXY protection. This vulnerability is due to an incomplete for CVE-2025-62718, This vulnerability is fixed in 1.15.1 and 0.31.1.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability enables SSRF via NO_PROXY bypass to loopback addresses, directly facilitating exploitation of public-facing applications that use Axios with unsanitized URLs.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
SI-2 requires timely flaw remediation, directly mitigating this Axios vulnerability by updating to patched versions 1.15.1 or 0.31.1.
SI-10 enforces validation of user-influenced target URLs to block loopback addresses in the 127.0.0.0/8 range that bypass NO_PROXY protections.
SC-7 implements boundary protections like firewalls or proxies to monitor and block SSRF attempts targeting internal loopback addresses.