Description
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember HTTP/2 serializes outbound frames through one unbounded queue consumed by writeLoop. When the peer stops reading, an unauthenticated HTTP/2 client can continue sending PING, SETTINGS, or DATA frames that cause Ember to enqueue acknowledgments or WINDOW_UPDATE frames faster than the writer drains them, exhausting heap memory on a server built with withHttp2. The shared behavior also affects an ember-client connected to a hostile HTTP/2 server, and the patch replaces the unbounded path with bounded, backpressured outbound queues. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| http4s | http4s | < 0.23.35, >= 1.0.0-M1, < 1.0.0-M47 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.http4s:http4s-ember-core_2.12 | < 0.23.35 | 0.23.35 | GHSA-8f3q-3jmv-7prw |
| Maven | org.http4s:http4s-ember-core_2.13 | < 0.23.35 | 0.23.35 | GHSA-8f3q-3jmv-7prw |
| Maven | org.http4s:http4s-ember-core_2.13 | >= 1.0.0-M1, < 1.0.0-M47 | 1.0.0-M47 | GHSA-8f3q-3jmv-7prw |
| Maven | org.http4s:http4s-ember-core_3 | < 0.23.35 | 0.23.35 | GHSA-8f3q-3jmv-7prw |
| Maven | org.http4s:http4s-ember-core_3 | >= 1.0.0-M1, < 1.0.0-M47 | 1.0.0-M47 | GHSA-8f3q-3jmv-7prw |