{"vulnerability": "cve-2026-69218", "sightings": [{"uuid": "c997b6b8-e159-4544-8110-ba33faea72a8", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-69218", "type": "seen", "source": "https://gist.github.com/alon710/1d7bf0359f0215ea04330c59b303d19c", "content": "# CVE-2026-69218: CVE-2026-69218: Denial of Service via Unbounded HTTP/2 Continuation Frame Buffering in http4s Ember\n\n> **CVSS Score:** 7.5\n> **Published:** 2026-09-15\n> **Full Report:** https://cvereports.com/reports/CVE-2026-69218\n\n## Summary\nA critical resource exhaustion vulnerability exists in the http4s Ember HTTP/2 server and client implementations. By failing to limit the size or quantity of incoming HTTP/2 CONTINUATION frames, the engine allows unauthenticated remote attackers to exhaust JVM heap memory, causing a complete Denial of Service.\n\n## TL;DR\nUnbounded HTTP/2 CONTINUATION frames cause JVM heap exhaustion and DoS in http4s Ember.\n\n## Exploit Status: POC\n\n## Technical Details\n\n- **CWE ID**: CWE-770\n- **Attack Vector**: Network (AV:N)\n- **CVSS v3.1**: 7.5 (High)\n- **Exploit Status**: poc\n- **KEV Status**: Not Listed\n\n## Affected Systems\n\n- http4s-ember-server\n- http4s-ember-client\n- **http4s-ember-core**: < 0.23.35 (Fixed in: `0.23.35`)\n- **http4s-ember-core**: >= 1.0.0-M1, < 1.0.0-M47 (Fixed in: `1.0.0-M47`)\n\n## Mitigation\n\n- Upgrade http4s library dependencies to patched versions (0.23.35 or 1.0.0-M47)\n- Deploy a reverse proxy such as Nginx or Envoy in front of http4s to handle the HTTP/2 frame layer\n- Apply strict request rate-limiting and connection limits at the edge firewall\n\n**Remediation Steps:**\n1. Identify all projects and microservices using org.http4s:http4s-ember-server or org.http4s:http4s-ember-client.\n2. Update build definitions (e.g., build.sbt) to use version 0.23.35 or 1.0.0-M47.\n3. Validate the fix by verifying that incoming headers exceeding configured limits trigger HTTP/2 EnhanceYourCalm (0xb) errors.\n4. Re-deploy the updated service instances and monitor JVM memory performance metrics.\n\n## References\n\n- [GHSA-cp4q-fqw9-4hf6: http4s Vulnerability Advisory](https://github.com/http4s/http4s/security/advisories/GHSA-cp4q-fqw9-4hf6)\n- [CVE-2026-69218 Record](https://www.cve.org/CVERecord?id=CVE-2026-69218)\n\n\n---\n*Generated by [CVEReports](https://cvereports.com/reports/CVE-2026-69218) - Automated Vulnerability Intelligence*", "creation_timestamp": "2026-09-16T09:31:31.539502Z"}]}