CVE-2023-49805 Uptime Kuma Missing Origin Validation in WebSockets
Attackers can bypass firewall protections and access the application via cross-origin WebSocket connections, especially in no-auth mode.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2023-49805?
CVE-2023-49805 is a medium-severity vulnerability in louislam uptime-kuma, published on 11 Dec 2023. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Uptime Kuma is an easy-to-use self-hosted monitoring tool. Prior to version 1.23.9, the application uses WebSocket (with Socket.io), but it does not verify that the source of communication is valid. This allows third-party website to access the application on behalf of their client. When connecting to the server using Socket.IO, the server does not validate the `Origin` header leading to other site being able to open connections to the server and communicate with it. Other websites still need to authenticate to access most features, however this can be used to circumvent firewall protections made in place by people deploying the application.
Without origin validation, Javascript executed from another origin would be allowed to connect to the application without any user interaction. Without login credentials, such a connection is unable to access protected endpoints containing sensitive data of the application. However, such a connection may allow attacker to further exploit unseen vulnerabilities of the application. Users with "No-auth" mode configured who are relying on a reverse proxy or firewall to provide protection to the application would be especially vulnerable as it would grant the attacker full access to the application.
In version 1.23.9, additional verification of the HTTP Origin header has been added to the socket.io connection handler. By default, if the `Origin` header is present, it would be checked against the Host header. Connection would be denied if the hostnames do not match, which would indicate that the request is cross-origin. Connection would be allowed if the `Origin` header is not present. Users can override this behavior by setting environment variable `UPTIME_KUMA_WS_ORIGIN_CHECK=bypass`.
Which versions are affected by CVE-2023-49805?
It affects 2 products.
Products include Dockge.kuma Dockge, Uptime.kuma Uptime Kuma.
How do I fix CVE-2023-49805?
No fix has been published for CVE-2023-49805 yet. Limit exposure of the affected software until one is available.
Is CVE-2023-49805 being exploited?
There is no known exploitation of CVE-2023-49805 in the wild and no public exploit code.
Other vulnerabilities in louislam uptime-kuma
Sources
Also known as GHSA-mj22-23ff-2hrr.