GHSA-67c6-q4j4-hccg
Flarum vulnerable to LFI and Blind SSRF via Avatar upload
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Packagist | flarum/core | < 1.8.0 | 1.8.0 |
| Packagist | flarum/framework | < 1.8.0 | 1.8.0 |
Details
As written in the advisory (Markdown source, shown as plain text).
## Impact
The Flarum forum software is affected by a vulnerability that allows an attacker to conduct a Blind SSRF attack or disclose any file on the server, even with a basic user account on any Flarum forum. By uploading a file containing a URL and spoofing the MIME type, an attacker can manipulate the application to execute unintended actions. The vulnerability is due to the behavior of the `intervention/image` package, which attempts to interpret the supplied file contents as a URL, which then fetches its contents. This allows an attacker to exploit the vulnerability to perform SSRF attacks, disclose local file contents, or conduct a blind oracle attack.
### Patches
This has been patched in Flarum **v1.8**.
## Workarounds
As a temporary workaround for the SSRF aspect of the vulnerability, one can disable PHP's `allow_url_fopen` which will prevent the fetching of external files via URLs.
### Credits
Adam Kues - [Assetnote](https://assetnote.io/)
References
External links from the advisory. They lead to third-party sites.