CVE-2026-67314
axios before 1.18.0 Prototype Pollution via auth subfields
axios versions >=1.15.2 and <1.18.0 contain prototype-pollution read-side gadgets in Basic auth subfield handling (lib/adapters/http.js and lib/helpers/resolveConfig.js). When an application is already affected by a separate prototype-pollution primitive and makes an axios request with an own auth object that omits the username and/or password properties, axios reads the inherited Object.prototype.username and Object.prototype.password values and uses them to construct an outbound 'Authorization: Basic ...' header. axios itself does not pollute prototypes. The practical impact is outbound request tampering: an attacker who controls the polluted prototype values can inject attacker-chosen Basic auth credentials or replace an existing Authorization header. Credential disclosure is only possible under additional application-specific conditions.
- Affected
- axios
- CVSS v4.0 VULNCHECK
- 6.3 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v4.0 GitHub
- 6.3 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N - CVSS v3.1 NVD
- 6.5 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L - EPSS
- 0.41% chance of exploitation in the next 30 days, 34th percentile
- Published
- 2026-08-01
- Updated
- 2026-08-03
Proof-of-concept exploits (1)
Security advisories
- axios/axios/security/advisories/GHSA-xj6q-8x83-jv6g
- https://www.vulncheck.com/advisories/axios-before-prototype-pollution-via-auth-subfields