CVE-2021-34650 in eID Easy Plugin
Summary
by MITRE • 09/21/2021
The eID Easy WordPress plugin is vulnerable to Reflected Cross-Site Scripting via the error parameter found in the ~/admin.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 4.6.
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Analysis
by VulDB Data Team • 09/29/2021
The eID Easy WordPress plugin version 4.6 and earlier contains a reflected cross-site scripting vulnerability that poses significant security risks to WordPress installations. This vulnerability exists within the admin.php file where the error parameter is not properly sanitized or validated, creating an opening for malicious actors to execute arbitrary web scripts within the context of authenticated admin sessions.
The technical flaw stems from insufficient input validation and output encoding practices within the plugin's administrative interface. When the error parameter is passed through the URL and subsequently rendered without proper sanitization, it allows attackers to inject malicious scripts that can be executed by other users who visit the affected page. This reflected XSS vulnerability operates by tricking users into clicking malicious links that contain script payloads, which are then executed in the victim's browser when the page loads.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to escalate privileges, steal session cookies, and potentially gain full administrative control over affected WordPress sites. Attackers can craft malicious URLs that, when clicked by administrators, would execute scripts that could steal authentication tokens, modify site content, or redirect users to phishing sites. The vulnerability is particularly dangerous in environments where administrators frequently visit administrative pages or where the plugin is widely used across multiple sites.
This vulnerability aligns with CWE-79 which categorizes cross-site scripting flaws as weaknesses in input validation and output encoding. The attack vector follows typical XSS patterns documented in the MITRE ATT&CK framework under technique T1566 for credential access through social engineering and T1059 for command and control through script injection. Organizations using the eID Easy plugin should immediately update to version 4.7 or later where this vulnerability has been patched, implement proper input validation measures, and consider network monitoring to detect potential exploitation attempts. Additionally, administrators should review user permissions and implement web application firewalls to mitigate potential exploitation of this and similar vulnerabilities.
The remediation process requires immediate patching of the vulnerable plugin version, followed by comprehensive security auditing of all installed plugins to identify similar vulnerabilities. Security teams should also establish monitoring procedures to detect suspicious parameter usage in administrative interfaces and implement proper content security policies to prevent script execution in administrative contexts. Regular security assessments of WordPress installations remain crucial for identifying and addressing such vulnerabilities before they can be exploited in real-world attacks.