CVE-2026-69218
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 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.
Not on KEV
Not in CISA's Known Exploited Vulnerabilities catalogue as of the last daily pull. Absence is not proof of safety.
0%
Chance of exploitation in the next 30 days, 39th percentile of all CVEs. A forecast; KEV outranks it.
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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No exposure census on this CVE's dispatches.
- nvd.nist.gov ↗
- first.org · EPSS ↗
- github.com/http4s/http4s/commit/6e8eccd64a6a74ab4811897881e95e0e1b3a818e ↗
- github.com/http4s/http4s/commit/f9dcca4f5a17992ac0972fafd7920f9bc12cdc51 ↗
- github.com/http4s/http4s/releases/tag/v0.23.35 ↗
- github.com/http4s/http4s/releases/tag/v1.0.0-M47 ↗
- github.com/http4s/http4s/security/advisories/GHSA-cp4q-fqw9-4hf6 ↗
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