CVE-2026-67319

axios before 0.33.0 (and 1.x before 1.18.0) can consume inherited properties from nested request option objects when the JavaScript process's Object.prototype has already been polluted by another component. While the top-level merged config uses a null prototype, nested plain objects such as auth and paramsSerializer are cloned into ordinary objects and read without own-property checks. When an application passes placeholder nested objects such as auth: {} or paramsSerializer: {}, inherited username/password values can cause silent injection of an Authorization: Basic header, and inherited encode/serialize values can alter query-string serialization (full serializer replacement requires a function-valued pollution primitive). This is exploitable only in the presence of pre-existing prototype pollution.

  • Published Aug 1, 2026
  • CVSS 6.3 medium
  • 0.3% chance of exploitation in the next 30 days (EPSS)
  • Public exploit code is available
  • A fix is available

Affected software

In the news

CVE-2026-67319 at the National Vulnerability Database