CVE-2026-115701: high-severity vulnerability in ninenines cowboy
Cowboy HTTP/1.1 Unbounded Buffering of Pipelined Data During Request Handling Enables Memory Exhaustion
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.5%
Allocation of Resources Without Limits or Throttling vulnerability in ninenines cowboy allows an unauthenticated remote attacker to exhaust connection process memory over HTTP/1.1.
Once a request has been received in full and its handler is still running, cowboy_http:parse/2 in src/cowboy_http.erl appends every further byte that arrives on the keep-alive connection to the connection buffer and returns to the receive loop without parsing it. The socket stays in active mode and no limit applies to this buffer: max_request_line_length, max_headers and the other parser limits only take effect once the handler returns and parsing resumes, and the only timer in this state is idle_timeout (default 60 seconds), which is reset on every received chunk. A client can therefore send an arbitrary amount of data on one connection for as long as the handler runs, and a few connections to an endpoint that holds requests open can drive the Erlang VM into out-of-memory conditions.
This issue affects cowboy: from 2.18.0 onward.
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
Affected products
ninenines · cowboyRelated CVEs — ninenines cowboy
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