{"api_version":"1","generated_at":"2026-06-22T03:59:37+00:00","cve":"CVE-2026-49336","urls":{"html":"https://cve.report/CVE-2026-49336","api":"https://cve.report/api/cve/CVE-2026-49336.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-49336","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-49336"},"summary":{"title":"@microsoft/kiota-http-fetchlibrary: Bearer token and Cookie leak across origin on redirect due to case-mismatched scrub in fetchRequestAdapter","description":"@microsoft/kiota-http-fetchlibrary provides TypeScript libraries for Kiota-generated API clients. In versions 1.0.0-preview.97 through 1.0.0-preview.101, `@microsoft/kiota-http-fetchlibrary`'s `RedirectHandler` is documented as stripping `Authorization` and `Cookie` from cross-origin redirect targets, but the default `scrubSensitiveHeaders` callback in `RedirectHandlerOptions` uses case-sensitive property deletion (`delete headers.Authorization`, `delete headers.Cookie`) on a headers object that `FetchRequestAdapter.getRequestFromRequestInformation` has already lower-cased. The delete therefore targets keys that do not exist, the scrub is a no-op, and any Bearer token or Cookie attached by a kiota-generated SDK is forwarded to an attacker-controlled host across a 30x redirect. This is reachable in the default middleware chain (`MiddlewareFactory.getDefaultMiddlewares`) with no custom configuration, and applies to every kiota-generated TypeScript SDK that uses `BaseBearerTokenAuthenticationProvider` or any other authentication provider that sets the `Authorization` request header. Version 1.0.0-preview.102 patches the issue.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-06-19 19:16:36","updated_at":"2026-06-19 19:16:36"},"problem_types":["CWE-178","CWE-200","CWE-178 CWE-178: Improper Handling of Case Sensitivity","CWE-200 CWE-200: Exposure of Sensitive Information to an Unauthorized Actor"],"metrics":[{"version":"4.0","source":"security-advisories@github.com","type":"Secondary","score":"5.5","severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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","data":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}},{"version":"4.0","source":"CNA","type":"DECLARED","score":"5.5","severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P","data":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":5.5,"baseSeverity":"MEDIUM","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE"}}],"references":[{"url":"https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974","name":"https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9","name":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49336","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49336","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"microsoft","product":"kiota-typescript","version":"affected >= 1.0.0-preview.97, < 1.0.0-preview.102","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"kiota-typescript","vendor":"microsoft","versions":[{"status":"affected","version":">= 1.0.0-preview.97, < 1.0.0-preview.102"}]}],"descriptions":[{"lang":"en","value":"@microsoft/kiota-http-fetchlibrary provides TypeScript libraries for Kiota-generated API clients. 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Version 1.0.0-preview.102 patches the issue."}],"metrics":[{"cvssV4_0":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":5.5,"baseSeverity":"MEDIUM","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-178","description":"CWE-178: Improper Handling of Case Sensitivity","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-200","description":"CWE-200: Exposure of Sensitive Information to an Unauthorized Actor","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-06-19T18:19:03.222Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9","tags":["x_refsource_CONFIRM"],"url":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9"},{"name":"https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974","tags":["x_refsource_MISC"],"url":"https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974"}],"source":{"advisory":"GHSA-396q-4vc8-28x9","discovery":"UNKNOWN"},"title":"@microsoft/kiota-http-fetchlibrary: Bearer token and Cookie leak across origin on redirect due to case-mismatched scrub in fetchRequestAdapter"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-49336","datePublished":"2026-06-19T18:19:03.222Z","dateReserved":"2026-05-29T14:35:45.902Z","dateUpdated":"2026-06-19T18:19:03.222Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-19 19:16:36","lastModifiedDate":"2026-06-19 19:16:36","problem_types":["CWE-178","CWE-200","CWE-178 CWE-178: Improper Handling of Case Sensitivity","CWE-200 CWE-200: Exposure of Sensitive Information to an Unauthorized Actor"],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"49336","Ordinal":"1","Title":"@microsoft/kiota-http-fetchlibrary: Bearer token and Cookie leak","CVE":"CVE-2026-49336","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"49336","Ordinal":"1","NoteData":"@microsoft/kiota-http-fetchlibrary provides TypeScript libraries for Kiota-generated API clients. In versions 1.0.0-preview.97 through 1.0.0-preview.101, `@microsoft/kiota-http-fetchlibrary`'s `RedirectHandler` is documented as stripping `Authorization` and `Cookie` from cross-origin redirect targets, but the default `scrubSensitiveHeaders` callback in `RedirectHandlerOptions` uses case-sensitive property deletion (`delete headers.Authorization`, `delete headers.Cookie`) on a headers object that `FetchRequestAdapter.getRequestFromRequestInformation` has already lower-cased. The delete therefore targets keys that do not exist, the scrub is a no-op, and any Bearer token or Cookie attached by a kiota-generated SDK is forwarded to an attacker-controlled host across a 30x redirect. This is reachable in the default middleware chain (`MiddlewareFactory.getDefaultMiddlewares`) with no custom configuration, and applies to every kiota-generated TypeScript SDK that uses `BaseBearerTokenAuthenticationProvider` or any other authentication provider that sets the `Authorization` request header. Version 1.0.0-preview.102 patches the issue.","Type":"Description","Title":"@microsoft/kiota-http-fetchlibrary: Bearer token and Cookie leak"}]}}}