{"items":[{"id":"NVI-00017860","kind":"vulnerability","title":"Http4s Ember HTTP/2: unbounded continuation frame accumulation","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-cp4q-fqw9-4hf6","CVE-2026-69218"],"plain_summary":"GitHub lists this reviewed advisory for org.http4s:http4s-ember-core_2.12, org.http4s:http4s-ember-core_2.13, org.http4s:http4s-ember-core_3, org.http4s:http4s-ember-core_2.13, org.http4s:http4s-ember-core_3. 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-743bb4950c66c113b5447d47a23ca39b"],"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":"2026-09-15T20:01:09.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-743bb4950c66c113b5447d47a23ca39b"}],"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-743bb4950c66c113b5447d47a23ca39b","url":"https://github.com/advisories/GHSA-cp4q-fqw9-4hf6","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-cp4q-fqw9-4hf6","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T19:09:30.244Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-743bb4950c66c113b5447d47a23ca39b"],"technology":"org.http4s:http4s-ember-core_2.12","known_exclusions":[],"conditions_summary":"When Ember receives an HTTP/2 `HEADERS` or `PUSH_PROMISE` frame without the `END_HEADERS` flag, it buffers the header block fragment and waits for subsequent `CONTINUATION` frames.  These accumulate unbounded until the connection closes. \n\n### Impact\n\nA remote, unauthenticated peer can exhaust the heap on any Ember endpoint that has HTTP/2 enabled:\n\n- **ember-server with `.withHttp2`**: any HTTP/2 client can trigger this against any reachable path (including paths that return 404).  No authentication is required because the attack completes before the request is decoded.\n- **ember-client with `.withHttp2`**:  a malicious or compromised origin server can trigger this via the response header block.  A single in-flight request is sufficient.\n\nMemory consumption is bounded only by the attacker's upload bandwidth and the connection lifetime.\n\n### Prerequisites\n\n- `EmberServerBuilder` configured with `.withHttp2`.\n    - For the server: the attacker can establish an HTTP/2 connection\n    - For the client: the application makes a request to an attacker-controlled origin.\nHTTP/2 incoming headers exceeding the configured size limit are buffer in order to generate an informative HTTP 413 resp","public_affected_ranges":["<= 0.23.34"]},{"certainty":"source_listed","source_ids":["sr-743bb4950c66c113b5447d47a23ca39b"],"technology":"org.http4s:http4s-ember-core_2.13","known_exclusions":[],"conditions_summary":"When Ember receives an HTTP/2 `HEADERS` or `PUSH_PROMISE` frame without the `END_HEADERS` flag, it buffers the header block fragment and waits for subsequent `CONTINUATION` frames.  These accumulate unbounded until the connection closes. \n\n### Impact\n\nA remote, unauthenticated peer can exhaust the heap on any Ember endpoint that has HTTP/2 enabled:\n\n- **ember-server with `.withHttp2`**: any HTTP/2 client can trigger this against any reachable path (including paths that return 404).  No authentication is required because the attack completes before the request is decoded.\n- **ember-client with `.withHttp2`**:  a malicious or compromised origin server can trigger this via the response header block.  A single in-flight request is sufficient.\n\nMemory consumption is bounded only by the attacker's upload bandwidth and the connection lifetime.\n\n### Prerequisites\n\n- `EmberServerBuilder` configured with `.withHttp2`.\n    - For the server: the attacker can establish an HTTP/2 connection\n    - For the client: the application makes a request to an attacker-controlled origin.\nHTTP/2 incoming headers exceeding the configured size limit are buffer in order to generate an informative HTTP 413 resp","public_affected_ranges":["<= 0.23.34"]},{"certainty":"source_listed","source_ids":["sr-743bb4950c66c113b5447d47a23ca39b"],"technology":"org.http4s:http4s-ember-core_3","known_exclusions":[],"conditions_summary":"When Ember receives an HTTP/2 `HEADERS` or `PUSH_PROMISE` frame without the `END_HEADERS` flag, it buffers the header block fragment and waits for subsequent `CONTINUATION` frames.  These accumulate unbounded until the connection closes. \n\n### Impact\n\nA remote, unauthenticated peer can exhaust the heap on any Ember endpoint that has HTTP/2 enabled:\n\n- **ember-server with `.withHttp2`**: any HTTP/2 client can trigger this against any reachable path (including paths that return 404).  No authentication is required because the attack completes before the request is decoded.\n- **ember-client with `.withHttp2`**:  a malicious or compromised origin server can trigger this via the response header block.  A single in-flight request is sufficient.\n\nMemory consumption is bounded only by the attacker's upload bandwidth and the connection lifetime.\n\n### Prerequisites\n\n- `EmberServerBuilder` configured with `.withHttp2`.\n    - For the server: the attacker can establish an HTTP/2 connection\n    - For the client: the application makes a request to an attacker-controlled origin.\nHTTP/2 incoming headers exceeding the configured size limit are buffer in order to generate an informative HTTP 413 resp","public_affected_ranges":["<= 0.23.34"]},{"certainty":"source_listed","source_ids":["sr-743bb4950c66c113b5447d47a23ca39b"],"technology":"org.http4s:http4s-ember-core_2.13","known_exclusions":[],"conditions_summary":"When Ember receives an HTTP/2 `HEADERS` or `PUSH_PROMISE` frame without the `END_HEADERS` flag, it buffers the header block fragment and waits for subsequent `CONTINUATION` frames.  These accumulate unbounded until the connection closes. \n\n### Impact\n\nA remote, unauthenticated peer can exhaust the heap on any Ember endpoint that has HTTP/2 enabled:\n\n- **ember-server with `.withHttp2`**: any HTTP/2 client can trigger this against any reachable path (including paths that return 404).  No authentication is required because the attack completes before the request is decoded.\n- **ember-client with `.withHttp2`**:  a malicious or compromised origin server can trigger this via the response header block.  A single in-flight request is sufficient.\n\nMemory consumption is bounded only by the attacker's upload bandwidth and the connection lifetime.\n\n### Prerequisites\n\n- `EmberServerBuilder` configured with `.withHttp2`.\n    - For the server: the attacker can establish an HTTP/2 connection\n    - For the client: the application makes a request to an attacker-controlled origin.\nHTTP/2 incoming headers exceeding the configured size limit are buffer in order to generate an informative HTTP 413 resp","public_affected_ranges":[">= 1.0.0-M1, <= 1.0.0-M46"]},{"certainty":"source_listed","source_ids":["sr-743bb4950c66c113b5447d47a23ca39b"],"technology":"org.http4s:http4s-ember-core_3","known_exclusions":[],"conditions_summary":"When Ember receives an HTTP/2 `HEADERS` or `PUSH_PROMISE` frame without the `END_HEADERS` flag, it buffers the header block fragment and waits for subsequent `CONTINUATION` frames.  These accumulate unbounded until the connection closes. \n\n### Impact\n\nA remote, unauthenticated peer can exhaust the heap on any Ember endpoint that has HTTP/2 enabled:\n\n- **ember-server with `.withHttp2`**: any HTTP/2 client can trigger this against any reachable path (including paths that return 404).  No authentication is required because the attack completes before the request is decoded.\n- **ember-client with `.withHttp2`**:  a malicious or compromised origin server can trigger this via the response header block.  A single in-flight request is sufficient.\n\nMemory consumption is bounded only by the attacker's upload bandwidth and the connection lifetime.\n\n### Prerequisites\n\n- `EmberServerBuilder` configured with `.withHttp2`.\n    - For the server: the attacker can establish an HTTP/2 connection\n    - For the client: the application makes a request to an attacker-controlled origin.\nHTTP/2 incoming headers exceeding the configured size limit are buffer in order to generate an informative HTTP 413 resp","public_affected_ranges":[">= 1.0.0-M1, <= 1.0.0-M46"]}],"null_published_at":"2026-11-05T19:10:21.476Z","source_updated_at":"2026-09-15T20:01:09.000Z","source_disclosed_at":"2026-09-15T20:01:08.000Z","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":"2026-11-01T19:09:30.244Z"}],"next_cursor":null,"snapshot_revision":"42594"}