Headline
GHSA-xv6x-456v-24xh: gotify/server vulnerable to Cross-site Scripting in the application image file upload
Impact
The XSS vulnerability allows authenticated users to upload .html files. With that, an attacker could execute client side scripts if another user opened a link, such as:
https://push.example.org/image/[alphanumeric string].html
An attacker could potentially take over the account of the user that clicked the link. Keep in mind, the Gotify UI won’t natively expose such a malicious link, so an attacker has to get the user to open the malicious link in a context outside of Gotify.
Patches
The vulnerability has been fixed in version 2.2.2.
Workarounds
You can block access to non image files via a reverse proxy in the ./image directory.
References
https://github.com/gotify/server/pull/534 https://github.com/gotify/server/pull/535
Thanks to rickshang (aka 无在无不在) for discovering and reporting this bug.
Impact
The XSS vulnerability allows authenticated users to upload .html files. With that, an attacker could execute client side scripts if another user opened a link, such as:
https://push.example.org/image/[alphanumeric string].html
An attacker could potentially take over the account of the user that clicked the link. Keep in mind, the Gotify UI won’t natively expose such a malicious link, so an attacker has to get the user to open the malicious link in a context outside of Gotify.
Patches
The vulnerability has been fixed in version 2.2.2.
Workarounds
You can block access to non image files via a reverse proxy in the ./image directory.
References
gotify/server#534
gotify/server#535
Thanks to rickshang (aka 无在无不在) for discovering and reporting this bug.
References
- GHSA-xv6x-456v-24xh
- https://nvd.nist.gov/vuln/detail/CVE-2022-46181
- gotify/server#534
- gotify/server#535
Related news
Gotify server is a simple server for sending and receiving messages in real-time per WebSocket. Versions prior to 2.2.2 contain an XSS vulnerability that allows authenticated users to upload .html files. An attacker could execute client side scripts **if** another user opened a link. The attacker could potentially take over the account of the user that clicked the link. The Gotify UI won't natively expose such a malicious link, so an attacker has to get the user to open the malicious link in a context outside of Gotify. The vulnerability has been fixed in version 2.2.2. As a workaround, you can block access to non image files via a reverse proxy in the `./image` directory.