# CVE-2026-72918: Rocket.Chat: Insecure implementation of websocket notifications

> Authenticated users can inject fake messages into other users' chats due to missing sender validation in WebSocket notifications.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 10 Aug 2026
- **Updated:** 11 Aug 2026
- **Also known as:** GHSA-27jx-236m-3f5j

## What is CVE-2026-72918?

CVE-2026-72918 is a medium-severity missing authorization vulnerability in RocketChat Rocket.Chat, published on 10 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 7.10.14, 8.0.8, 8.1.7, 8.2.7, 8.3.7, 8.4.5, 8.5.2, and 8.6.1, the stream-notify-user stream in the WebSocket protocol allows an authenticated user to write arbitrary notification bodies because the sender is not checked, and the client-side UI can create an ephemeral fake message in another user's currently open chat. This issue is fixed in versions 7.10.14, 8.0.8, 8.1.7, 8.2.7, 8.3.7, 8.4.5, 8.5.2, and 8.6.1.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-72918?


## How do I fix CVE-2026-72918?

No fix has been published for CVE-2026-72918 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-72918 being exploited?

There is no known exploitation of CVE-2026-72918 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72918 and fix it if it is affected.

What it is: CVE-2026-72918 is a medium-severity missing authorization vulnerability in RocketChat Rocket.Chat, published on 10 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-72918 in the wild and no public exploit code.

Affected product: RocketChat Rocket.Chat. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-72918/ (Markdown: https://insights.sbomify.com/CVE-2026-72918/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72918
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72918
- OSV: https://osv.dev/vulnerability/CVE-2026-72918

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72918/
Summaries are generated and may contain mistakes; the official description above is the record.