CVE-2026-101909

Impact

Prototype pollution lets attackers change form-field naming/data, cause request failures, alter Blob handling, and—when combined with function-injection—execute code (potential RCE).

Triage

Exploitable

At runtime

Attack vector

network

Weakness

• CWE-1321 Common Weakness

Can a WAF block it?

Partly. See why

Executive summary (AI-written)

CVE-2026-101909 represents a significant vulnerability within the widely-used Axios library, which serves as a critical tool for making HTTP requests in both Node.js and browser applications. With a CVSS score of 8.3, rated as major severity, this vulnerability exposes systems to potential code execution through prototype pollution, enabling attackers to manipulate data serialization and alter the behavior of applications relying on this library. Given the pervasive nature of Axios, the risk extends across various industries and applications, heightening the need for immediate attention. Organizations utilizing affected versions of Axios must prioritize patching to versions 0.34.0 or greater, or 1.20.0 or greater, to mitigate the risk of exploitation. Failure to address this vulnerability could lead to significant operational disruptions, data manipulation, or unauthorized code execution, underscoring the importance of maintaining secure coding practices and application dependencies in a landscape where cyber threats are increasingly sophisticated.

Technical analysis (AI-written)

CVE-2026-101909 is characterized as a prototype pollution vulnerability within the 'toFormData' function of the Axios library. Prototype pollution occurs when an attacker can manipulate an object's prototype, allowing them to modify or introduce new properties to objects that may inadvertently affect application logic. With an assigned CVSS score of 8.3, this vulnerability can lead to severe implications including code execution in the same process, particularly when combined with other attack vectors like function injection. The affected versions include Axios 0.28.0 to 0.33.x and 1.15.1 to 1.19.x, impacting diverse environments from Node.js applications to browser-based applications bundling the affected library. The proof of concept for exploitation is relatively straightforward for attackers familiar with JavaScript, as they can leverage the pollution to redefine form field names or overall data structures within requests, potentially causing application behavior to deviate from intended functionality. Complexity for exploitation varies based on the application architecture and the attacker’s access level, but remote code execution (RCE) possibilities amplify the concern, given that an attacker might gain control over an application’s execution environment. This is particularly critical for high-trust applications managing sensitive data or key operations. Mitigating this vulnerability is straightforward, as patches are available. Organizations are advised to upgrade to Axios versions >=0.34.0 or >=1.20.0 immediately. Additionally, a thorough audit of dependency trees is recommended to identify any indirect dependencies that may still utilize vulnerable versions of Axios. Such proactive measures are critical in patching vulnerabilities and enforcing secure coding practices. Given Axios's ubiquity in web development, the ripple-effect of this vulnerability can be significant. Security teams should conduct a risk assessment to determine the potential impact on their specific applications and consider implementing strict input validation and sanitation to bolster defenses against similar vulnerabilities in the future. Regular updates and reviews of third-party libraries are essential components of a robust security posture.

Action required

Patch when possible

WAF and other mitigations

Remediation steps (AI-written)

Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.