{"items":[{"id":"NVI-00013065","kind":"vulnerability","title":"undici vulnerable to Denial of Service via unrequested WebSocket subprotocol","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-rfgv-xxqx-mfg5","CVE-2026-19534"],"plain_summary":"GitHub lists this reviewed advisory for undici, undici, undici. 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-4f9ad20bdbed8ac29efdeb2705c0876b"],"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":"CVSS","as_of":"2026-09-29T18:21:41.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4f9ad20bdbed8ac29efdeb2705c0876b"}],"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-4f9ad20bdbed8ac29efdeb2705c0876b","url":"https://github.com/advisories/GHSA-rfgv-xxqx-mfg5","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-rfgv-xxqx-mfg5","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:24:25.558Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4f9ad20bdbed8ac29efdeb2705c0876b"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nThe undici WebSocket client throws an uncaught `TypeError` during the opening handshake when a server's `101` response includes a `Sec-WebSocket-Protocol` header that the client never requested. The throw occurs in a `queueMicrotask` callback with no surrounding `try`/`catch`, so it propagates as an uncaught exception and terminates the Node.js process. This is a remote, unauthenticated denial of service against any application that opens a WebSocket to an attacker controlled or compromised server, or over a plaintext `ws://` connection subject to a machine-in-the-middle. It affects the default `new WebSocket(url)` usage, where no subprotocol is requested. Per RFC 6455 section 4.1, an unrequested subprotocol must fail the connection, not crash it.\n\nAll releases starting at undici 6.7.0 are affected.\n\n### Patches\n\nUpgrade to undici 6.28.1, 7.29.1, or 8.10.2.\n\n### Workarounds\n\nNo workaround is available. The fix must be applied through an upgrade.","public_affected_ranges":[">= 6.7.0, < 6.28.1"]},{"certainty":"source_listed","source_ids":["sr-4f9ad20bdbed8ac29efdeb2705c0876b"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nThe undici WebSocket client throws an uncaught `TypeError` during the opening handshake when a server's `101` response includes a `Sec-WebSocket-Protocol` header that the client never requested. The throw occurs in a `queueMicrotask` callback with no surrounding `try`/`catch`, so it propagates as an uncaught exception and terminates the Node.js process. This is a remote, unauthenticated denial of service against any application that opens a WebSocket to an attacker controlled or compromised server, or over a plaintext `ws://` connection subject to a machine-in-the-middle. It affects the default `new WebSocket(url)` usage, where no subprotocol is requested. Per RFC 6455 section 4.1, an unrequested subprotocol must fail the connection, not crash it.\n\nAll releases starting at undici 6.7.0 are affected.\n\n### Patches\n\nUpgrade to undici 6.28.1, 7.29.1, or 8.10.2.\n\n### Workarounds\n\nNo workaround is available. The fix must be applied through an upgrade.","public_affected_ranges":[">= 7.0.0, < 7.29.1"]},{"certainty":"source_listed","source_ids":["sr-4f9ad20bdbed8ac29efdeb2705c0876b"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nThe undici WebSocket client throws an uncaught `TypeError` during the opening handshake when a server's `101` response includes a `Sec-WebSocket-Protocol` header that the client never requested. The throw occurs in a `queueMicrotask` callback with no surrounding `try`/`catch`, so it propagates as an uncaught exception and terminates the Node.js process. This is a remote, unauthenticated denial of service against any application that opens a WebSocket to an attacker controlled or compromised server, or over a plaintext `ws://` connection subject to a machine-in-the-middle. It affects the default `new WebSocket(url)` usage, where no subprotocol is requested. Per RFC 6455 section 4.1, an unrequested subprotocol must fail the connection, not crash it.\n\nAll releases starting at undici 6.7.0 are affected.\n\n### Patches\n\nUpgrade to undici 6.28.1, 7.29.1, or 8.10.2.\n\n### Workarounds\n\nNo workaround is available. The fix must be applied through an upgrade.","public_affected_ranges":[">= 8.0.0, < 8.10.2"]}],"null_published_at":"2026-11-01T07:29:12.914Z","source_updated_at":"2026-09-29T18:21:41.000Z","source_disclosed_at":"2026-09-29T18:21:33.000Z","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":"2026-11-01T07:24:25.558Z"}],"next_cursor":null,"snapshot_revision":"42594"}