{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-84303", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-09-01T16:17:43.078Z", "datePublished": "2026-09-01T18:14:37.870Z", "dateUpdated": "2026-09-02T19:14:49.353Z"}, "containers": {"cna": {"title": "gRPC-Go: xDS RBAC HTTP Filter bypass via mixed-case Header Matching and gRFC A41 validation evasion", "problemTypes": [{"descriptions": [{"cweId": "CWE-178", "lang": "en", "description": "CWE-178: Improper Handling of Case Sensitivity", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-863", "lang": "en", "description": "CWE-863: Incorrect Authorization", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 6.3, "baseSeverity": "MEDIUM", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N", "version": "4.0"}}], "references": [{"name": "https://github.com/grpc/grpc-go/security/advisories/GHSA-qc2q-p7wx-3px3", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/grpc/grpc-go/security/advisories/GHSA-qc2q-p7wx-3px3"}, {"name": "https://github.com/grpc/grpc-go/pull/9332", "tags": ["x_refsource_MISC"], "url": "https://github.com/grpc/grpc-go/pull/9332"}, {"name": "https://github.com/grpc/grpc-go/pull/9335", "tags": ["x_refsource_MISC"], "url": "https://github.com/grpc/grpc-go/pull/9335"}, {"name": "https://github.com/grpc/grpc-go/commit/db9482836c298f234c896cf82ab68cafc78237f8", "tags": ["x_refsource_MISC"], "url": "https://github.com/grpc/grpc-go/commit/db9482836c298f234c896cf82ab68cafc78237f8"}, {"name": "https://github.com/grpc/grpc-go/commit/ebba6f3f1b206e2b4dc4d1d5a96d18430302c2fe", "tags": ["x_refsource_MISC"], "url": "https://github.com/grpc/grpc-go/commit/ebba6f3f1b206e2b4dc4d1d5a96d18430302c2fe"}, {"name": "https://github.com/grpc/grpc-go/releases/tag/v1.83.1", "tags": ["x_refsource_MISC"], "url": "https://github.com/grpc/grpc-go/releases/tag/v1.83.1"}], "affected": [{"vendor": "grpc", "product": "grpc-go", "versions": [{"version": "< 1.83.1", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-01T18:14:37.870Z"}, "descriptions": [{"lang": "en", "value": "gRPC-Go is the Go language implementation of gRPC. Prior to 1.83.1, the xDS RBAC HTTP filter in internal/xds/httpfilter/rbac/rbac.go does not lowercase header matcher names in normalizeHeaderMatcher even though incoming metadata keys are lowercase. A DENY policy using a mixed-case name such as X-Role or User-Agent therefore does not match and fails open, allowing requests that should be rejected. The same case mismatch permits :Scheme or Grpc-Status to evade gRFC A41 validation and prevents Host from being rewritten to :authority. This issue is fixed in version 1.83.1."}], "source": {"advisory": "GHSA-qc2q-p7wx-3px3", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-02T19:14:42.460152Z", "id": "CVE-2026-84303", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-02T19:14:49.353Z"}}]}}

{}

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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.83.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "grpc-go", "source": "cna", "vendor": "grpc"}, "product": "grpc-go", "vendor": "grpc"}], "created": "2026-09-02T03:15:04.318918+00:00", "updated": "2026-09-02T03:45:04.274047+00:00", "vendors": ["grpc", "grpc$PRODUCT$grpc-go"]}