{"id":"CVE-2026-101908","state":"PUBLISHED","title":"Axios: Prototype pollution gadget in fetch adapter can alter outbound requests","description":"Axios is a promise-based HTTP client for the browser and Node.js. From 1.7.0 until 1.20.0, the fetch adapter constructs a Request with sanitized resolvedOptions but then calls fetch with the original fetchOptions. A separate same-process prototype-pollution flaw populates Object.prototype.headers so fetchOptions.headers resolves through inheritance. The inherited fetchOptions.headers value overrides the sanitized Request headers through the second argument to fetch after Request construction. Attacker-controlled request headers can alter authorization, caching, metadata-service access, or application-specific behavior. This issue is fixed in version 1.20.0.","publishedAt":"2026-09-28T17:38:55.303Z","updatedAt":"2026-09-28T18:15:41.687Z","severity":{"score":6.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["axios axios"],"affected":[{"vendor":"axios","product":"axios","versions":[{"version":">= 1.7.0, < 1.20.0","status":"affected"}]}],"references":["https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8","https://github.com/axios/axios/pull/11141","https://github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a","https://github.com/axios/axios/releases/tag/v1.20.0"],"weaknesses":["CWE-1321"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/101xxx/CVE-2026-101908.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-101908","state":"PUBLISHED","datePublished":"2026-09-28T17:38:55.303Z","dateUpdated":"2026-09-28T18:15:41.687Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-09-28T15:55:37.907Z"},"containers":{"cna":{"title":"Axios: Prototype pollution gadget in fetch adapter can alter outbound requests","descriptions":[{"lang":"en","value":"Axios is a promise-based HTTP client for the browser and Node.js. From 1.7.0 until 1.20.0, the fetch adapter constructs a Request with sanitized resolvedOptions but then calls fetch with the original fetchOptions. A separate same-process prototype-pollution flaw populates Object.prototype.headers so fetchOptions.headers resolves through inheritance. The inherited fetchOptions.headers value overrides the sanitized Request headers through the second argument to fetch after Request construction. Attacker-controlled request headers can alter authorization, caching, metadata-service access, or application-specific behavior. This issue is fixed in version 1.20.0."}],"affected":[{"vendor":"axios","product":"axios","versions":[{"version":">= 1.7.0, < 1.20.0","status":"affected"}]}],"references":[{"url":"https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8","name":"https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/axios/axios/pull/11141","name":"https://github.com/axios/axios/pull/11141","tags":["x_refsource_MISC"]},{"url":"https://github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a","name":"https://github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a","tags":["x_refsource_MISC"]},{"url":"https://github.com/axios/axios/releases/tag/v1.20.0","name":"https://github.com/axios/axios/releases/tag/v1.20.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"HIGH","subAvailabilityImpact":"NONE","baseScore":6.9,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1321","lang":"en","description":"CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-28T17:38:55.303Z"},"source":{"advisory":"GHSA-vh66-26gq-q6x8","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/axios/axios/security/advisories/GHSA-vh66-26gq-q6x8","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-28T18:14:22.792981Z","id":"CVE-2026-101908","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-28T18:15:41.687Z"}}]}}}