Adminer 4.16.0 through 6.0.1 contain a pre-authentication Server-Side Request Forgery (SSRF) vulnerability in the optional Elasticsearch driver (plugins/drivers/elastic.php), fixed in 6.0.2. Because adminer/include/auth.inc.php invokes Driver::connect() before the login result is validated, an unauthenticated attacker who submits crafted auth[server], auth[username], and auth[password] parameters can cause the Adminer server to issue an HTTP GET request (via get_url()/file_get_contents()) to an arbitrary reachable host and port. The driver validates only general server syntax and does not block loopback, private, link-local, or other reserved addresses; if no port is given it appends the default 9200, and Adminers generic port check rejects ports below 1024. Selected JSON error fields from non-2xx Elasticsearch-style responses, as well as connection failures, are rendered on the login page, providing a port-scanning oracle and enabling internal network reconnaissance and service fingerprinting. Exploitation requires that the optional Elasticsearch driver be explicitly deployed (e.g., via the adminer/elastic.php template or an adminer_object() configuration; it is not loaded in a default build) and that PHP allow_url_fopen be enabled.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Adminer | Ubuntu | upstream | * |