ninenines cowboy src/cowboy_http.erl cowboy_http:parse allocation of resources

Summaryinfo

A vulnerability has been found in ninenines cowboy and classified as problematic. This vulnerability affects the function cowboy_http:parse of the file src/cowboy_http.erl. The manipulation leads to allocation of resources. This vulnerability is traded as CVE-2026-115701. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in ninenines cowboy (the affected version unknown). It has been rated as problematic. This issue affects the function cowboy_http:parse of the file src/cowboy_http.erl. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. Impacted is availability. The summary by CVE is:

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.

It is possible to read the advisory at cna.erlef.org. The identification of this vulnerability is CVE-2026-115701 since 10/26/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

• ninenines

Name

• cowboy

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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