CVE-2023-45820 is a medium-severity (CVSS 5.9) CWE-755 vulnerability in directus. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for directus — see the affected versions and patch details below.
Directus crashes on invalid WebSocket message
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-45820.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
directusnpmDescription
Summary
It seems that any Directus installation that has websockets enabled can be crashed if the websocket server receives an invalid frame. This could probably be posted as an issue and I might even be able to put together a pull request for a fix (if only I had some extra time...), but I decided to instead post as a vulnerability just for the maintainers, since this seemingly can be used to crash any live Directus server if websockets are enabled, so public disclosure is not a good idea until the issue is fixed.
Details
The fix for this seems quite simple; the websocket server just needs to properly catch the error instead of crashing the server. See for example: https://github.com/websockets/ws/issues/2098
PoC
- Start a fresh Directus server (using for example the compose file here: https://docs.directus.io/self-hosted/docker-guide.html). Enable websockets by setting
WEBSOCKETS_ENABLED: 'true'environment variable. - run a separate node app somewhere else to send an invalid frame to the server:
const WebSocket = require("ws");
const websocket = new WebSocket("ws://0.0.0.0:8055/websocket");
websocket.on("open", function () {
const chunk = Buffer.from("a180", "hex");
websocket._socket.write(chunk);
});
Impact
The server crashes with an error: RangeError: Invalid WebSocket frame: RSV2 and RSV3 must be clear. Server needs to be manually restarted to get back online (if there's no recovery mechanism in place, as there often isn't with simple node servers). This was confirmed on a local server, and additionally I was able to crash our staging server with the same code, just pointing to our staging Directus server running at fly.io. It seems to also crash servers running in the directus.cloud service. I created https://websocket-test.directus.app/, pointed the above script to the websocket url of that instance and the server does crash for a while. It seems that in there there's a mechanism for bringing the server back up quite fast, but it would be quite trivial for anyone to DoS any server running in directus.cloud by just spamming these invalid frames to the server.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | directus | ≥ 10.4.0&&< 10.6.2 | 10.6.2npm install directus@10.6.2 |
Affected Products
directusmonospaceResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for directus, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update directus to 10.6.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-45820 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2023-45820 in your dependencies?
Find it across npm, including transitive dependencies.