{"items":[{"id":"NVI-00013857","kind":"vulnerability","title":"gRPC-Go: xDS RBAC HTTP Filter bypass via mixed-case Header Matching and gRFC A41 validation evasion","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-qc2q-p7wx-3px3","CVE-2026-84303"],"plain_summary":"GitHub lists this reviewed advisory for google.golang.org/grpc. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-07b1179a0593d1fca28251e5b066d48b"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"EPSS","as_of":"2026-11-05T12:03:04.000Z","value":"0.311%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.24091. Missing scores are unknown.","source_id":"sr-07b1179a0593d1fca28251e5b066d48b"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-111d6aef971d40a68cc8b964353c48c1","url":"https://github.com/advisories/GHSA-qc2q-p7wx-3px3","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qc2q-p7wx-3px3","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:20:31.767Z"},{"id":"sr-07b1179a0593d1fca28251e5b066d48b","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-84303","publisher":"FIRST EPSS","observed_at":"2026-11-06T07:17:46.400Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-111d6aef971d40a68cc8b964353c48c1"],"technology":"google.golang.org/grpc","known_exclusions":[],"conditions_summary":"### Summary\nA vulnerability in the xDS RBAC HTTP filter implementation in grpc-go allows remote attackers to bypass authorization policies (specifically DENY rules) by using mixed-case or canonical-case header matchers (e.g., X-Role instead of x-role). Additionally, the safety guards introduced by gRFC A41 to block grpc- prefixed headers can be evaded via variations in casing (e.g., Grpc-Status).\n\n### Impact\nWhen an operator defines an RBAC policy referencing headers containing uppercase letters (e.g. X-Role), grpc-go fails to match incoming metadata keys because they are unconditionally lowercased. Because of this case-sensitivity mismatch, a policy designed to block requests containing specific header values fails open: the rule is evaluated as a non-match, and traffic that should have been rejected is served.\n\nFurthermore, gRFC A41 requires rejecting configuration schemas specifying header matchers starting with grpc-. Because this check is executed case-sensitively in grpc-go, attackers can bypass the validation by specifying titles like Grpc-Status.\n\n### Patches\nThe problem is fixed in `master` and in the 1.83.1 release.","public_affected_ranges":["<= 1.83.0"]}],"null_published_at":"2026-11-08T15:11:49.406Z","source_updated_at":"2026-09-08T20:50:23.000Z","source_disclosed_at":"2026-09-08T20:50:21.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-02T02:20:31.767Z"},{"id":"NVI-00013857","kind":"vulnerability","title":"gRPC-Go: xDS RBAC HTTP Filter bypass via mixed-case Header Matching and gRFC A41 validation evasion","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-qc2q-p7wx-3px3","CVE-2026-84303"],"plain_summary":"GitHub lists this reviewed advisory for google.golang.org/grpc. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-111d6aef971d40a68cc8b964353c48c1"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-111d6aef971d40a68cc8b964353c48c1","url":"https://github.com/advisories/GHSA-qc2q-p7wx-3px3","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qc2q-p7wx-3px3","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:20:31.767Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-111d6aef971d40a68cc8b964353c48c1"],"technology":"google.golang.org/grpc","known_exclusions":[],"conditions_summary":"### Summary\nA vulnerability in the xDS RBAC HTTP filter implementation in grpc-go allows remote attackers to bypass authorization policies (specifically DENY rules) by using mixed-case or canonical-case header matchers (e.g., X-Role instead of x-role). Additionally, the safety guards introduced by gRFC A41 to block grpc- prefixed headers can be evaded via variations in casing (e.g., Grpc-Status).\n\n### Impact\nWhen an operator defines an RBAC policy referencing headers containing uppercase letters (e.g. X-Role), grpc-go fails to match incoming metadata keys because they are unconditionally lowercased. Because of this case-sensitivity mismatch, a policy designed to block requests containing specific header values fails open: the rule is evaluated as a non-match, and traffic that should have been rejected is served.\n\nFurthermore, gRFC A41 requires rejecting configuration schemas specifying header matchers starting with grpc-. Because this check is executed case-sensitively in grpc-go, attackers can bypass the validation by specifying titles like Grpc-Status.\n\n### Patches\nThe problem is fixed in `master` and in the 1.83.1 release.","public_affected_ranges":["<= 1.83.0"]}],"null_published_at":"2026-11-02T10:00:37.161Z","source_updated_at":"2026-09-08T20:50:23.000Z","source_disclosed_at":"2026-09-08T20:50:21.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-02T02:20:31.767Z"}],"next_cursor":null,"snapshot_revision":"42594"}