CVE-2025-34102 is a critical remote code execution vulnerability affecting the PHP version of Crypttech's CryptoLog product, which has been discontinued since 2009. The vulnerability arises from a chained exploitation involving two distinct flaws: an SQL injection (CWE-89) in the login.php script and a command injection (CWE-78) in the logshares_ajax.php script. An unauthenticated attacker can exploit the SQL injection vulnerability by submitting specially crafted input via the 'user' POST parameter to bypass authentication controls. This allows the attacker to gain unauthorized access to the application as if logged in. Once authenticated, the attacker can leverage the command injection vulnerability by manipulating the 'lsid' POST parameter in the logshares_ajax.php endpoint. This parameter is improperly sanitized and allows execution of arbitrary operating system commands using the shell $(...) syntax. Consequently, the attacker can execute commands with the privileges of the web server user, effectively gaining shell access remotely without any user interaction or prior authentication. The vulnerability is specific to the PHP version of CryptoLog; the ASP.NET version released after 2009 does not contain this exploitation path. The CVSS v4.0 score is 9.3 (critical), reflecting the vulnerability's ease of exploitation (no authentication or user interaction required), high impact on confidentiality, integrity, and availability, and the ability to fully compromise the affected system. No official patches are available due to the product's discontinued status, and no known exploits have been reported in the wild yet. The vulnerability also relates to improper access control (CWE-306) and improper input validation (CWE-20), compounding the risk.

For European organizations still running the vulnerable PHP version of CryptoLog, this vulnerability poses a severe risk. Successful exploitation can lead to complete system compromise, including unauthorized access to sensitive logs or data managed by CryptoLog, potential lateral movement within the network, and the deployment of further malware or ransomware. The ability to execute arbitrary commands remotely without authentication means attackers can establish persistent backdoors or exfiltrate confidential information. This is particularly critical for sectors handling sensitive or regulated data such as finance, healthcare, and government agencies in Europe. Additionally, the lack of vendor support and patches increases the risk exposure, as organizations must rely on internal mitigations or migration strategies. The vulnerability could also be leveraged in supply chain attacks if CryptoLog is integrated into broader logging or monitoring infrastructures. Given the criticality and ease of exploitation, the threat could disrupt business continuity and lead to significant financial and reputational damage.

Since CryptoLog PHP versions are discontinued and no patches are available, European organizations should prioritize the following mitigations: 1) Immediate identification and inventory of any CryptoLog PHP deployments within their environment. 2) Disable or isolate affected CryptoLog instances from external network access to prevent remote exploitation. 3) Migrate to the supported ASP.NET version of CryptoLog or alternative secure logging solutions that receive regular security updates. 4) Implement Web Application Firewalls (WAFs) with custom rules to detect and block suspicious SQL injection and command injection payloads targeting the 'user' and 'lsid' POST parameters. 5) Employ network segmentation to limit the impact of a potential compromise, restricting the web server's access to critical internal systems. 6) Conduct thorough security audits and penetration tests focusing on legacy PHP applications to identify similar injection flaws. 7) Monitor logs and network traffic for anomalous activities indicative of exploitation attempts, such as unusual POST requests or shell command executions. 8) Educate development and operations teams about secure coding practices to prevent injection vulnerabilities in legacy and new applications.