Adminer multi_query Incorrect Check of Function Return Value Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Adminer. Authentication is required to exploit this vulnerability. The specific flaw exists within the multi_query method. The issue results from an incorrect check of a function return value. An attacker can leverage this vulnerability to execute code in the context of the web server. Was ZDI-CAN-28201.

Adminer before 5.4.3 contains a cookie injection vulnerability that allows attackers to manipulate cookie attributes by injecting arbitrary values through the unsanitized X-Forwarded-Prefix HTTP header used in Set-Cookie path attributes. Attackers can exploit a misconfigured reverse proxy to downgrade SameSite protection and enable cross-origin authenticated requests, bypassing cookie security controls.

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.