Cyber Resilience

CVE-2026-42043

SSRF in Axios ≤ 0.31.1

Public PoCSSRF
Published
24 April 2026
Modified
13 August 2026
Patch / advisory
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
EPSS Score 0.0066 48th percentile
Risk Priority 55 floored blend · peak EPSS

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 Proxy (T1090); ranked at the 48th 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 map to AC-16 (Security and Privacy Attributes) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

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

Vulnerability Data

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)…

more

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 Techniques

T1090 Proxy Command And Control
Adversaries may use a connection proxy to direct network traffic between systems or act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure.
T1090.002 External Proxy Command And Control
Adversaries may use an external proxy to act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure.
T1090.001 Internal Proxy Command And Control
Adversaries may use an internal proxy to direct command and control traffic between two or more systems in a compromised environment.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-62718Same product: Axios Axios
CVE-2025-27152Same product: Axios Axios
CVE-2026-42038Same product: Axios Axios
CVE-2024-39338Same product: Axios Axios
CVE-2026-44494Same product: Axios Axios
CVE-2026-44492Same product: Axios Axios
CVE-2026-42042Same product: Axios Axios
CVE-2026-40175Same product: Axios Axios
CVE-2023-45857Same product: Axios Axios
CVE-2026-42037Same product: Axios Axios

Affected Assets

axios
axios
≤ 0.31.1 · 1.0.0 — 1.15.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.5.2
  • V4.4.2
  • V3.2.1
  • V3.5.1

Mitigating Controls (NIST 800-53 r5) AI

Associating and preserving security attributes such as original source identity prevents the loss of provenance that creates the confused deputy.

Information flow enforcement requires preserving and checking source attributes before forwarding requests outside the trust boundary.

Strict validity checks on inputs directly stop overly permissive allow lists from being used as the protection mechanism.

Access enforcement directly stops a component from acting on forwarded requests without verifying original source authorizations.

Boundary protection limits and inspects external forwarding, reducing the ability of an intermediary to act as an unintended proxy.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-04 mostly match
prevents

Proper conveyance and verification of original identity assertions directly prevents loss of request source when forwarding.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require rigorous allow-list design and testing that prevents permissive input validation.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.AA-05 partial match
prevents

Enforcing least-privilege authorizations on forwarded requests reduces confused-deputy abuse even if source identity is lost.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect overly broad allow-lists, but does not inherently prevent their creation.

prevents

Access-control rules can limit which upstream identities may cause the product to act on their behalf, reducing confused-deputy risk.

prevents

Proper identity management ensures the original requester identity is preserved and validated before the product forwards requests.

degrades

Explicit access-rights assignment can restrict the product’s ability to act as an unintended proxy for external actors.

prevents

Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.

degrades

Privileged-access controls limit the rights the product may exercise on behalf of upstream callers, mitigating confused-deputy abuse.

References