CVE-2018-15843 in GetSimple
Summary
by MITRE
GetSimple CMS 3.3.14 has XSS via the admin/edit.php "Add New Page" field.
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Analysis
by VulDB Data Team • 05/04/2023
The vulnerability CVE-2018-15843 represents a cross-site scripting flaw within GetSimple CMS version 3.3.14 that specifically affects the administrative interface. This issue manifests in the admin/edit.php page where users can add new pages through a dedicated field input mechanism. The flaw enables malicious actors to inject arbitrary JavaScript code that executes within the context of other users' browsers who access the compromised administrative interface. Such vulnerabilities are particularly dangerous in content management systems where administrators have elevated privileges and access to sensitive system functions.
The technical implementation of this vulnerability stems from insufficient input validation and output sanitization within the page creation functionality. When administrators navigate to the "Add New Page" field in the admin/edit.php interface, the application fails to properly sanitize user-supplied input before rendering it back to the browser. This allows attackers to craft malicious payloads that exploit the browser's trust in the application's output, leading to unauthorized code execution in the victim's browser context. The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications where untrusted data is improperly handled during output generation.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with a potential foothold for more sophisticated attacks within the CMS environment. An attacker who successfully exploits this vulnerability could potentially steal administrator session cookies, redirect users to malicious sites, or inject additional malicious code to escalate privileges further. The attack vector is particularly concerning because it targets the administrative interface where users typically have elevated permissions, potentially allowing attackers to modify content, create backdoors, or access sensitive system information. This vulnerability can be exploited through various means including social engineering, where administrators might be tricked into submitting malicious content through the legitimate page creation interface.
Mitigation strategies for this vulnerability should include immediate patching of the GetSimple CMS to version 3.3.15 or later, which contains the necessary fixes for the XSS vulnerability. Organizations should also implement input validation at multiple layers including client-side and server-side sanitization of all user inputs. Security measures should include content security policies to prevent unauthorized script execution, regular security audits of administrative interfaces, and user education regarding suspicious activities. The ATT&CK framework categorizes this vulnerability under T1059.007 for scripting languages and T1566 for social engineering techniques that could be employed to exploit such weaknesses. Additionally, implementing web application firewalls and regular security monitoring can help detect and prevent exploitation attempts targeting this specific vulnerability.