CVE-2025-29421 is a high-severity vulnerability affecting PerfreeBlog version 4.0.11. The vulnerability exists in the getThemeFileContent function, which allows an attacker to perform arbitrary file read operations. This means that an unauthenticated remote attacker can exploit this flaw over the network without any user interaction to read arbitrary files on the server hosting the vulnerable PerfreeBlog instance. The vulnerability is classified under CWE-284, indicating an authorization bypass or insufficient access control issue. The CVSS v3.1 base score is 7.5, reflecting a high impact on confidentiality with no impact on integrity or availability. The attack vector is network-based (AV:N), with low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The scope is unchanged (S:U), meaning the vulnerability affects resources managed by the vulnerable component only. Although no known exploits are currently reported in the wild and no patches have been linked yet, the presence of arbitrary file read can lead to exposure of sensitive configuration files, source code, credentials, or other critical data stored on the server, potentially facilitating further attacks such as privilege escalation or lateral movement.

For European organizations using PerfreeBlog 4.0.11, this vulnerability poses a significant risk to the confidentiality of their data. Attackers could gain unauthorized access to sensitive files, including configuration files containing database credentials or API keys, which could lead to data breaches or compromise of backend systems. Since the vulnerability requires no authentication or user interaction, it can be exploited remotely and at scale, increasing the risk of widespread data leakage. This is particularly critical for organizations handling personal data under GDPR regulations, as unauthorized disclosure could result in regulatory penalties and reputational damage. Additionally, exposure of source code or internal files could facilitate further exploitation or targeted attacks against the affected organizations. The lack of a patch or mitigation at the time of disclosure increases the urgency for organizations to implement compensating controls.

Given the absence of an official patch, European organizations should immediately implement network-level protections such as web application firewalls (WAFs) with custom rules to detect and block suspicious requests targeting the getThemeFileContent function or attempts to access arbitrary files. Restricting access to the PerfreeBlog administrative interface and theme files to trusted IP addresses via network segmentation or VPN can reduce exposure. Organizations should audit and harden file permissions on the server to ensure that sensitive files are not readable by the web server process beyond what is necessary. Monitoring web server logs for unusual file access patterns can help detect exploitation attempts early. If feasible, temporarily disabling or restricting the vulnerable functionality until a patch is available is recommended. Additionally, organizations should maintain regular backups and prepare incident response plans to quickly address any potential compromise.