CVE-2026-54556: fallo de gravedad alta en http4s
Http4s: HTTP/2 Denial of Service with Ember Backend
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 8.2epss 0.5%
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, an unauthenticated HTTP/2 peer can cause an out-of-memory denial of service in the Ember backend with HTTP/2 enabled. The Hpack wrapper in ember-core/shared/src/main/scala/org/http4s/ember/core/h2/Hpack.scala concatenates HEADERS and CONTINUATION frame fragments and decodes them into a single List, but maxHeaderSize accounting does not include indexed headers or HPACK per-header overhead. A small compressed header block can therefore expand into a much larger decoded representation that remains in memory for processing. Servers exposed to untrusted HTTP/2 traffic and clients directed to an untrusted HTTP/2 server are affected, and concurrent malicious connections can exhaust the process heap. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Productos afectados
http4s · http4sorg.http4s · http4s-ember-core_2.12org.http4s · http4s-ember-core_2.13org.http4s · http4s-ember-core_3CVEs relacionadas — http4s
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