CVE-2026-32688
Gravedad CVSS v4.0:
ALTA
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
27/04/2026
Última modificación:
27/04/2026
Descripción
*** Pendiente de traducción *** Allocation of Resources Without Limits or Throttling vulnerability in elixir-plug plug_cowboy allows unauthenticated remote denial of service via atom table exhaustion.<br />
<br />
Plug.Cowboy.Conn.conn/1 in lib/plug/cowboy/conn.ex calls String.to_atom/1 on the value returned by :cowboy_req.scheme/1. For HTTP/2 connections, cowlib passes the client-supplied :scheme pseudo-header value through verbatim without validation. Each unique value permanently allocates a new entry in the BEAM atom table. Since atoms are never garbage-collected and the atom table has a fixed limit (default 1,048,576), an unauthenticated attacker can exhaust the table by sending HTTP/2 requests with unique :scheme values, causing the Erlang VM to abort with system_limit and taking down the entire node.<br />
<br />
This vulnerability does not affect HTTP/1.1, where cowboy derives the scheme from the listener type rather than from a client-supplied header.<br />
<br />
This issue affects plug_cowboy: from 2.0.0 before 2.8.1.
Impacto
Puntuación base 4.0
8.70
Gravedad 4.0
ALTA