CVE-2025-34315 is a stored cross-site scripting (XSS) vulnerability identified in IPFire, an open-source firewall and security distribution. The flaw exists in versions prior to 2.29 (Core Update 198) and arises from improper neutralization of input during web page generation (CWE-79). Specifically, the vulnerability is triggered when an authenticated user updates the remote syslog server address via the REMOTELOG_ADDR parameter in an HTTP POST request to /cgi-bin/logs.cgi/config.dat. The input provided in REMOTELOG_ADDR is stored without proper sanitization or encoding and later rendered in the web interface. This allows malicious JavaScript code injected by an attacker to execute in the context of other users who access the affected configuration page. The vulnerability requires authentication but no user interaction beyond that. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L - low privileges), no user interaction (UI:P - partial), and limited scope impact (SI:L). The impact is primarily on confidentiality and integrity within the web interface, enabling potential session hijacking, credential theft, or unauthorized actions. Although no known exploits are currently reported in the wild, the vulnerability poses a risk to environments where multiple administrators access the IPFire management interface. IPFire is widely used in small to medium enterprises and some critical infrastructure environments as a firewall and network security gateway, making this vulnerability relevant for organizations relying on it for perimeter defense. The lack of a patch link suggests that users should upgrade to IPFire 2.29 or later, where the issue is resolved. Proper input validation and output encoding are essential to prevent such XSS vulnerabilities.

For European organizations, this vulnerability could lead to unauthorized execution of malicious scripts within the IPFire web interface, potentially compromising administrative sessions and allowing attackers to manipulate firewall configurations or steal sensitive information. This could degrade network security posture, cause operational disruptions, or facilitate further attacks within the network. Organizations with multiple administrators or remote management setups are particularly at risk. The medium severity rating reflects that while the vulnerability requires authentication, the ease of exploitation and potential for privilege escalation within the management interface could have significant consequences. Critical infrastructure operators and enterprises relying on IPFire for network security could face increased risk of targeted attacks exploiting this flaw to gain footholds or disrupt services.

1. Upgrade IPFire installations to version 2.29 (Core Update 198) or later, where the vulnerability is fixed. 2. Restrict access to the IPFire web interface to trusted administrators only, using network segmentation, VPNs, or IP whitelisting. 3. Enforce strong authentication mechanisms and monitor administrative access logs for suspicious activity. 4. Implement web application firewalls (WAF) or intrusion detection systems (IDS) to detect and block malicious payloads targeting the REMOTELOG_ADDR parameter. 5. Conduct regular security audits and penetration testing focused on the IPFire management interface. 6. Educate administrators about the risks of stored XSS and safe input handling practices. 7. If immediate upgrade is not possible, consider disabling remote syslog configuration via the web interface or sanitizing inputs at the proxy level as a temporary workaround.