The Apollo Router is a configurable, high-performance graph router written in Rust to run a federated supergraph that uses Apollo Federation. Affected versions are subject to a Denial-of-Service (DoS) type vulnerability which causes the Router to panic and terminate when a multi-part response is sent. When users send queries to the router that uses the @defer or Subscriptions, the Router will panic.
To be vulnerable, users of Router must have a coprocessor with coprocessor.supergraph.response configured in their router.yaml and also to support either @defer or Subscriptions.  
Router version 1.33.0 has a fix for this vulnerability. https://github.com/apollographql/router/pull/4014 fixes the issue.
For affected versions, avoid using the coprocessor supergraph response:
# do not use this stage in your coprocessor configuration
coprocessor:
  supergraph:
    response:
Or you can disable defer and subscriptions support:
# disable defer and subscriptions:
supergraph:
  defer_support: false # enabled by default
subscription:
  enabled: false # disabled by default
and continue to use the coprocessor supergraph response.
https://github.com/apollographql/router/issues/4013
{
    "nvd_published_at": "2023-10-18T22:15:09Z",
    "severity": "HIGH",
    "github_reviewed_at": "2023-10-19T16:08:10Z",
    "github_reviewed": true,
    "cwe_ids": [
        "CWE-703",
        "CWE-754"
    ]
}