ewe is a Gleam web server. Versions 0.8.0 through 3.0.4 contain a bug in the handle_trailers function where rejected trailer headers (forbidden or undeclared) cause an infinite loop. When handle_trailers encounters such a trailer, three code paths (lines 520, 523, 526) recurse with the original buffer (rest) instead of advancing past the rejected header (Buffer(header_rest, 0)), causing decoder.decode_packet to re-parse the same header on every iteration.
The resulting loop has no timeout or escape — the BEAM process permanently wedges at 100% CPU. Any application that calls ewe.read_body on chunked requests is affected, and this is exploitable by any unauthenticated remote client before control returns to application code, making an application-level workaround impossible. This issue is fixed in version 3.0.5.
Attack Parameters
Impact Assessment
CVSS Vector v3.1
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Vshakitskiy Ewe
cpe:2.3:a:vshakitskiy:ewe:*:*:*:*:*:*:*:*
|
0.8.0
|
3.0.5
|