EEF-CVE-2026-71562

httpc does not bound server-supplied numeric header values before integer conversion

## Summary Improper Validation of Specified Quantity in Input vulnerability in Erlang/OTP inets httpc allows a malicious or compromised HTTP server to degrade availability by returning a numeric header whose value is a very long run of digits. `httpc_handler.erl` converts the server-supplied `Content-Length` with `list_to_integer/1` before comparing it against `max_body_size`, so the size check cannot protect the conversion, and the option defaults to `nolimit` in any case. The same unbounded conversion appears in `httpc_response:format_response/1` for `Content-Length` and in `httpc_response:get_ms_from_retry_after/1` for `Retry-After`, which is guarded only by a check that the first character is a digit. A value of up to roughly 1.26 million digits converts successfully and costs the requesting process hundreds of milliseconds of arbitrary-precision arithmetic per response. The conversion function is documented to accept integers of any size, so bounding the input is the caller's responsibility. This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 5.10 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2. Whether OTP before OTP 17.0, corresponding to inets before 5.10, is affected is unknown.