Overview
CVE-2025-12186 identifies a Stored Cross-Site Scripting (XSS) vulnerability within the Weekly Planner plugin for WordPress. This flaw affects versions up to and including 1.0. The vulnerability allows authenticated attackers with administrator-level permissions (or above) to inject malicious JavaScript code into the plugin’s settings. This injected script will then execute whenever a user accesses a page or area where the plugin renders these compromised settings. Crucially, this vulnerability primarily affects multi-site WordPress installations and single-site installations where the unfiltered_html capability has been disabled.
Technical Details
The root cause of this vulnerability lies in the insufficient input sanitization and output escaping within the Weekly Planner plugin’s administrative settings. Specifically, when an administrator configures the plugin’s settings, the plugin fails to properly sanitize the input data before storing it in the database. Subsequently, when the plugin retrieves and displays these settings, it neglects to properly escape the output, allowing any malicious JavaScript code embedded within the settings to be executed in the user’s browser.
An attacker can exploit this by injecting malicious JavaScript payloads into vulnerable settings fields. These payloads can then perform actions such as stealing user cookies, redirecting users to phishing sites, or even defacing the website.
CVSS Analysis
The Common Vulnerability Scoring System (CVSS) assigns CVE-2025-12186 a score of 4.4, classifying it as a MEDIUM severity vulnerability.
- CVSS Vector: (This would be the full vector string, but it’s speculative for this example) Let’s assume: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N
- Explanation:
- AV:N (Attack Vector: Network): The vulnerability is exploitable over the network.
- AC:L (Attack Complexity: Low): The attack requires little specialized access or restrictive conditions.
- PR:H (Privileges Required: High): An attacker needs administrator privileges to exploit this.
- UI:R (User Interaction: Required): User interaction is required. An administrator has to view the page that is displaying the settings.
- S:U (Scope: Unchanged): An exploited vulnerability cannot affect resources beyond the security scope managed by the security authority of the vulnerable component.
- C:L (Confidentiality: Low): There is limited information disclosure.
- I:L (Integrity: Low): There is limited modification of data.
- A:N (Availability: None): There is no impact to availability.
Possible Impact
Successful exploitation of this vulnerability can lead to several negative consequences:
- Account Takeover: An attacker could steal administrator cookies and hijack administrator accounts.
- Website Defacement: Malicious scripts could be used to alter the appearance and content of the website.
- Malware Distribution: The injected scripts could redirect users to websites hosting malware.
- Phishing Attacks: Attackers could use the vulnerability to inject phishing forms designed to steal user credentials.
Mitigation and Patch Steps
The most effective way to mitigate this vulnerability is to update the Weekly Planner plugin to a patched version that addresses the XSS issue. Check the WordPress plugin repository for an updated version. If an update is not yet available, consider the following temporary mitigations:
- Disable the Plugin: If the Weekly Planner plugin is not essential, temporarily disabling it can eliminate the risk.
- Monitor Administrator Activity: Carefully monitor administrator accounts for any suspicious activity.
- Web Application Firewall (WAF): Implement a WAF with rules that can detect and block XSS attacks.
- Restrict unfiltered_html capability: Ensure that untrusted administrators do not have the unfiltered_html capability.
