CVE-2025-58098 is a vulnerability classified under CWE-201, which involves the insertion of sensitive information into sent data. It affects Apache HTTP Server versions 2.4.65 and earlier when Server Side Includes (SSI) are enabled in conjunction with mod_cgid, but not mod_cgi. The vulnerability arises because the server passes the shell-escaped query string to the #exec cmd="..." directives within SSI. This behavior can cause sensitive information, such as query parameters or environment variables, to be inadvertently included in the output sent to clients. This leakage can expose confidential data to unauthorized users, potentially leading to information disclosure attacks. The issue was identified and addressed in Apache HTTP Server version 2.4.66, which corrects the handling of query strings in this context. No public exploits have been reported to date, but the vulnerability poses a risk especially in environments where SSI and mod_cgid are actively used. The vulnerability does not require authentication but does require specific server configurations to be exploitable. The lack of a CVSS score necessitates an assessment based on impact and exploitability factors.

For European organizations, the primary impact of CVE-2025-58098 is the risk of sensitive information disclosure through web servers running vulnerable Apache HTTP Server versions with SSI and mod_cgid enabled. This can compromise confidentiality by exposing query strings or other sensitive data embedded in server responses. Organizations handling personal data, financial information, or intellectual property are particularly at risk, as leaked data could facilitate further attacks or regulatory non-compliance under GDPR. The vulnerability could affect web applications that rely on SSI for dynamic content generation, potentially undermining trust and causing reputational damage. While the vulnerability does not directly enable remote code execution, the information disclosure could be leveraged by attackers for targeted attacks. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially for critical infrastructure and public sector entities in Europe that commonly use Apache HTTP Server. The impact on availability and integrity is minimal, but confidentiality impact is significant.

The primary mitigation is to upgrade Apache HTTP Server to version 2.4.66 or later, where the vulnerability is fixed. Organizations should audit their web server configurations to identify the use of Server Side Includes (SSI) combined with mod_cgid and assess whether mod_cgi is enabled or not. If SSI is not essential, consider disabling it to reduce attack surface. Additionally, review and sanitize query string usage in SSI directives to prevent unintended data exposure. Employ strict access controls and logging on web servers to detect anomalous requests that might exploit this vulnerability. For environments where immediate upgrade is not feasible, consider implementing web application firewalls (WAFs) with rules to block suspicious SSI exec commands containing query strings. Regularly monitor Apache security advisories for updates and patches. Finally, conduct penetration testing focused on SSI and mod_cgid configurations to verify the absence of sensitive data leakage.