Adminer has an Unauthenticated Persistent DoS via Array Injection in ?script=version Endpoint
Adminer is open-source database management software. Adminer v5.4.1 and earlier has a version check mechanism where adminer.org sends signed version info via JavaScript postMessage, which the browser then POSTs to ?script=version. This endpoint lacks origin validation and accepts POST data from any source. An attacker can POST version[] parameter which PHP converts to an array. On next page load, openssl_verify() receives this array instead of string and throws TypeError, returning HTTP 500 to all users. Upgrade to Adminer 5.4.2.
Adminer 4.8.1, when using Monolog for logging, allows a Denial of Service (memory consumption) via a crafted serialized payload (e.g., using s:1000000000), leading to a PHP Object Injection issue. Remote, unauthenticated attackers can trigger this by sending a malicious serialized object, which forces excessive memory usage, rendering Adminer’s interface unresponsive and causing a server-level DoS. While the server may recover after several minutes, multiple simultaneous requests can cause a complete crash requiring manual intervention.
Adminer and AdminerEvo are vulnerable to SSRF via database connection fields. This could allow an unauthenticated remote attacker to enumerate or access systems the attacker would not otherwise have access to. Adminer is no longer supported, but this issue was fixed in AdminerEvo version 4.8.4.
Improper Access Control in Adminer versions 1.12.0 to 4.6.2 (fixed in version 4.6.3) allows an attacker to achieve Arbitrary File Read on the remote server by requesting the Adminer to connect to a remote MySQL database.