# CVE-2026-73561: Hub: Unauthenticated WebSocket RPC Waiter Resource Exhaustion

> Unauthenticated WebSocket connections cause resource exhaustion via uncancelled timers, leading to server unavailability in the Hub library.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-g5vv-q72c-7j78

## What is CVE-2026-73561?

CVE-2026-73561 is a high-severity denial of service vulnerability in anephenix hub, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Hub is a Node.js WebSocket server and client with added features. Prior to 0.2.16, every incoming unauthenticated WebSocket connection triggers loadDefaultConnectionEventListeners to call requestClientId, which calls rpc.send for the get-client-id action and pushes a request into RPC.requests. The RPC.waitForReply function starts a setInterval polling loop every 10 milliseconds that is cleared only after a matching reply; if the client remains silent and closes, the timer and pending request stay allocated because the socket close path does not cancel them. Repeated connections therefore cause unbounded timers and heap entries, exhausting CPU and memory and making the server unavailable. This issue is fixed in version 0.2.16.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-73561?

2 open source packages ship an affected version, including @anephenix/hub.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@anephenix/hub` | npm | All versions | 0.2.16 |
| `@anephenix/hub` | npm | All versions | 0.2.16 |

## How do I fix CVE-2026-73561?

Upgrade @anephenix/hub to 0.2.16 or later.

## Is CVE-2026-73561 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73561 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73561 and fix it if it is affected.

What it is: CVE-2026-73561 is a high-severity denial of service vulnerability in anephenix hub, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73561 exists.

Affected packages and fixed versions:
- @anephenix/hub (npm): affected all versions; fixed in 0.2.16
- @anephenix/hub (npm): affected all versions; fixed in 0.2.16

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-73561/ (Markdown: https://insights.sbomify.com/CVE-2026-73561/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73561
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73561
- OSV: https://osv.dev/vulnerability/CVE-2026-73561

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73561/
Summaries are generated and may contain mistakes; the official description above is the record.