CVE Catalog

CVE-2026-69664

HighCVSS 8.7
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Elevated risk
0.69%

51th percentile - higher than 51% of all known CVEs

Summary

A vulnerability in the HTTP server (inets httpd) in Erlang/OTP allows an unauthenticated remote attacker to cause a denial of service (DoS) by sending a request with a chunked body whose chunk-size line is not a hexadecimal number. The worker handling the connection is never released and no timeout reclaims it, so repeating such requests across connections occupies all available workers, blocking legitimate clients. The default configuration is affected and no authentication is required.

Risk Assessment

An attacker can easily cause a complete denial of service of the HTTP service, potentially disrupting applications and systems relying on this server. The lack of required authentication increases the risk of exploitation by anyone with network access.

Recommendation

Immediately upgrade Erlang/OTP to a patched version (OTP 27.3.4.17, 28.5.0.6, or 29.0.6) and update the inets package accordingly. If upgrading is not possible, consider temporarily disabling the httpd server or restricting access to it.

Related vulnerabilities

Original NVD description (English source)

Missing Release of Resource after Effective Lifetime vulnerability in Erlang/OTP inets httpd allows an unauthenticated remote attacker to cause denial of service by sending a request with a chunked body whose chunk-size line is not a hexadecimal number. The worker serving the connection is never released and no timeout reclaims it, so repeating the request across connections occupies every available worker and denies service to legitimate clients. No authentication is required and the default configuration is affected. The chunk-size line must arrive in a write separate from the headers. When the body accompanies the headers, httpd_request_handler:handle_body/3 calls http_chunk:decode/3 inside a try ... catch throw:Error, so the {error, {chunk_size, _}} thrown by http_chunk:decode_size/4 is answered with 400 Bad Request. When the chunk size arrives later, the decoder is resumed through a bare catch in httpd_request_handler:handle_info/2, which converts the throw into a return value rather than raising it; the resulting error tuple is then treated as the next decoder continuation, the socket is re-armed, and the worker waits for data that never comes. The request timeout has already been cancelled at the point the headers were accepted, and the periodic byte-rate check is only armed when minimum_bytes_per_second is configured, which it is not by default. This issue affects OTP from OTP 18.1.4 before OTP 27.3.4.17, OTP 28.5.0.6, and OTP 29.0.6, corresponding to inets from 6.0.3 before 9.3.2.7, 9.6.2.3, and 9.7.2.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS