{"items":[{"id":"NVI-00008946","kind":"vulnerability","title":"undici WebSocket client vulnerable to Denial of Service via failed HTTP/2 handshake","revision":5,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-qq8j-7v2v-3rwp","CVE-2026-109855"],"plain_summary":"GitHub lists this reviewed advisory for 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-01498a748dc0e22795a9a600b04de72b"],"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},{"summary":"The original advisory lists fixed boundaries 8.11.2 for undici. Confirm the publisher’s latest guidance.","source_ids":["sr-a7d95053328aafce936dbcbdb201a49b"],"action_type":"vendor_patch","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":"2026-10-27T16:09:47.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4319865a6edf3c13cef06a0a86387097"},{"kind":"CVSS","as_of":"2026-10-19T20:46:49.400Z","value":"7.5 HIGH (3.1)","meaning":"ce714d77-add3-4f53-aff5-83d477b104bb severity; no combined Null risk score.","source_id":"sr-6170c94b3d1378f7fe89baf6b0281890"},{"kind":"EPSS","as_of":"2026-11-05T12:03:04.000Z","value":"0.279%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.20445. Missing scores are unknown.","source_id":"sr-01498a748dc0e22795a9a600b04de72b"}],"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-4319865a6edf3c13cef06a0a86387097","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:51.534Z"},{"id":"sr-a7d95053328aafce936dbcbdb201a49b","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-11-02T09:56:44.726Z"},{"id":"sr-6170c94b3d1378f7fe89baf6b0281890","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-109855","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-109855","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-03T09:58:37.778Z"},{"id":"sr-01498a748dc0e22795a9a600b04de72b","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-2026-109855","publisher":"FIRST EPSS","observed_at":"2026-11-06T00:24:57.628Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4319865a6edf3c13cef06a0a86387097"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":[">= 8.11.0, < 8.11.2"]},{"certainty":"source_listed","source_ids":["sr-a7d95053328aafce936dbcbdb201a49b"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":["SEMVER: introduced 8.11.0; fixed 8.11.2"]}],"null_published_at":"2026-11-07T07:07:42.512Z","source_updated_at":"2026-10-27T16:09:47.000Z","source_disclosed_at":"2026-10-27T16:09:45.000Z","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":"2026-10-31T21:56:51.534Z"},{"id":"NVI-00008946","kind":"vulnerability","title":"undici WebSocket client vulnerable to Denial of Service via failed HTTP/2 handshake","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-qq8j-7v2v-3rwp","CVE-2026-109855"],"plain_summary":"GitHub lists this reviewed advisory for 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-46aa2fb277dcbac5111d6c3cc23ae325"],"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},{"summary":"The original advisory lists fixed boundaries 8.11.2 for undici. Confirm the publisher’s latest guidance.","source_ids":["sr-a7d95053328aafce936dbcbdb201a49b"],"action_type":"vendor_patch","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":"2026-10-27T16:09:47.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4319865a6edf3c13cef06a0a86387097"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.279%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.20376. Missing scores are unknown.","source_id":"sr-46aa2fb277dcbac5111d6c3cc23ae325"}],"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-4319865a6edf3c13cef06a0a86387097","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:51.534Z"},{"id":"sr-a7d95053328aafce936dbcbdb201a49b","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-11-02T09:56:44.726Z"},{"id":"sr-46aa2fb277dcbac5111d6c3cc23ae325","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-2026-109855","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.374Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4319865a6edf3c13cef06a0a86387097"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":[">= 8.11.0, < 8.11.2"]},{"certainty":"source_listed","source_ids":["sr-a7d95053328aafce936dbcbdb201a49b"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":["SEMVER: introduced 8.11.0; fixed 8.11.2"]}],"null_published_at":"2026-11-02T20:21:10.348Z","source_updated_at":"2026-10-27T16:09:47.000Z","source_disclosed_at":"2026-10-27T16:09:45.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T21:56:51.534Z"},{"id":"NVI-00008946","kind":"vulnerability","title":"undici WebSocket client vulnerable to Denial of Service via failed HTTP/2 handshake","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-qq8j-7v2v-3rwp","CVE-2026-109855"],"plain_summary":"GitHub lists this reviewed advisory for 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-46aa2fb277dcbac5111d6c3cc23ae325"],"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":"2026-10-27T16:09:47.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4319865a6edf3c13cef06a0a86387097"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.279%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.20376. Missing scores are unknown.","source_id":"sr-46aa2fb277dcbac5111d6c3cc23ae325"}],"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-4319865a6edf3c13cef06a0a86387097","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:51.534Z"},{"id":"sr-46aa2fb277dcbac5111d6c3cc23ae325","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-2026-109855","publisher":"FIRST EPSS","observed_at":"2026-10-31T22:06:15.374Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4319865a6edf3c13cef06a0a86387097"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":[">= 8.11.0, < 8.11.2"]}],"null_published_at":"2026-10-31T23:18:17.236Z","source_updated_at":"2026-10-27T16:09:47.000Z","source_disclosed_at":"2026-10-27T16:09:45.000Z","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":"2026-10-31T21:56:51.534Z"},{"id":"NVI-00008946","kind":"vulnerability","title":"undici WebSocket client vulnerable to Denial of Service via failed HTTP/2 handshake","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-qq8j-7v2v-3rwp","CVE-2026-109855"],"plain_summary":"GitHub lists this reviewed advisory for 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-4319865a6edf3c13cef06a0a86387097"],"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":"2026-10-27T16:09:47.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4319865a6edf3c13cef06a0a86387097"}],"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-4319865a6edf3c13cef06a0a86387097","url":"https://github.com/advisories/GHSA-qq8j-7v2v-3rwp","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-qq8j-7v2v-3rwp","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:51.534Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4319865a6edf3c13cef06a0a86387097"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nundici's experimental WebSocket client (enabled by default via `allowH2: true`) crashes the Node.js process when it connects to a malicious server over HTTP/2. If the server answers the WebSocket upgrade with a response that fails handshake validation, undici aborts the request, but the abort is a no-op because the request is already marked completed, so the underlying `ClientHttp2Stream` is left open with no error listener. When the server then destroys the connection, the orphaned stream emits an unhandled `error` and the process exits. A remote, unauthenticated server can therefore deny service to any client that opens a WebSocket to it over HTTP/2. undici 8.11.0 and 8.11.1 are affected; the regression was introduced in 8.11.0.\n\n### Patches\n\nUpgrade to `8.11.2`.\n\n### Workarounds\n\nSet `allowH2: false` to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers, until upgrading.","public_affected_ranges":[">= 8.11.0, < 8.11.2"]}],"null_published_at":"2026-10-31T22:13:27.123Z","source_updated_at":"2026-10-27T16:09:47.000Z","source_disclosed_at":"2026-10-27T16:09:45.000Z","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":"2026-10-31T21:56:51.534Z"}],"next_cursor":null,"snapshot_revision":"42594"}