{"id":"CVE-2026-69218","title":"Http4s is a Scala interface for HTTP services","summary":"Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, When Ember receives an HTTP/2 HEADERS or PUSH_PROMISE frame without END_HEADERS, H2Connection buffers the header block and subsequent CONTINUATION fragments w…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-770"],"vendor":"http4s","product":"http4s","affected":["http4s < 0.23.35","http4s >= 1.0.0-M1, < 1.0.0-M47"],"patched":["org.http4s:http4s-ember-core_2.12 0.23.35","org.http4s:http4s-ember-core_2.13 0.23.35","org.http4s:http4s-ember-core_3 0.23.35","org.http4s:http4s-ember-core_2.13 1.0.0-M47","org.http4s:http4s-ember-core_3 1.0.0-M47"],"published":"2026-09-15","updated":"2026-09-17","sourceUpdated":"2026-09-17T17:16:46.710","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-69218","references":[{"url":"https://github.com/http4s/http4s/commit/6e8eccd64a6a74ab4811897881e95e0e1b3a818e","label":"security-advisories@github.com"},{"url":"https://github.com/http4s/http4s/commit/f9dcca4f5a17992ac0972fafd7920f9bc12cdc51","label":"security-advisories@github.com"},{"url":"https://github.com/http4s/http4s/releases/tag/v0.23.35","label":"security-advisories@github.com"},{"url":"https://github.com/http4s/http4s/releases/tag/v1.0.0-M47","label":"security-advisories@github.com"},{"url":"https://github.com/http4s/http4s/security/advisories/GHSA-cp4q-fqw9-4hf6","label":"security-advisories@github.com"},{"url":"https://github.com/advisories/GHSA-cp4q-fqw9-4hf6"}],"tags":["nvd","cve.org","ghsa","maven"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-09-17T16:46:52.034934Z"},"epss":0.0046,"epssPercentile":0.39179,"aliases":["GHSA-cp4q-fqw9-4hf6"],"ecosystem":"maven","ingestedAt":"2026-09-15T19:42:58.832Z","slug":"CVE-2026-69218","body":"## Overview\n\nHttp4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, When Ember receives an HTTP/2 HEADERS or PUSH_PROMISE frame without END_HEADERS, H2Connection buffers the header block and subsequent CONTINUATION fragments without a size bound. A remote peer can keep an incomplete block open and exhaust heap memory before request decoding, affecting an ember-server or ember-client configured with withHttp2. The remediation tracks accumulated size against SETTINGS_MAX_HEADER_LIST_SIZE derived from EmberServerBuilder.maxHeaderSize or EmberClientBuilder.maxResponseHeaderSize, sends GOAWAY when the limit is exceeded, and applies receiveHeadersTimeout to incomplete blocks. This issue is fixed in versions 0.23.35 and 1.0.0-M47.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-69218)\n\nAffected packages:\n\n- `org.http4s:http4s-ember-core_2.12 <= 0.23.34`\n- `org.http4s:http4s-ember-core_2.13 <= 0.23.34`\n- `org.http4s:http4s-ember-core_3 <= 0.23.34`\n- `org.http4s:http4s-ember-core_2.13 >= 1.0.0-M1, <= 1.0.0-M46`\n- `org.http4s:http4s-ember-core_3 >= 1.0.0-M1, <= 1.0.0-M46`\n\nPatched in:\n\n- `org.http4s:http4s-ember-core_2.12 0.23.35`\n- `org.http4s:http4s-ember-core_2.13 0.23.35`\n- `org.http4s:http4s-ember-core_3 0.23.35`\n- `org.http4s:http4s-ember-core_2.13 1.0.0-M47`\n- `org.http4s:http4s-ember-core_3 1.0.0-M47`\n\nSource: https://github.com/advisories/GHSA-cp4q-fqw9-4hf6","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}