CVE-2018-19933 in Bolt
Summary
by MITRE
Bolt CMS <3.6.2 allows XSS via text input click preview button as demonstrated by the Title field of a Configured and New Entry.
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Analysis
by VulDB Data Team • 03/23/2025
Bolt CMS versions prior to 3.6.2 contain a cross-site scripting vulnerability that arises from insufficient input validation and output sanitization when processing user-supplied text data. This vulnerability specifically manifests when users interact with the click preview button functionality within the content management interface, particularly affecting the Title field of both configured and new entries. The flaw represents a classic injection vulnerability where maliciously crafted input can be executed within the browser context of authenticated users, potentially leading to unauthorized actions or data theft.
The technical implementation of this vulnerability stems from the application's failure to properly escape or filter special characters in user-entered text before rendering it in the preview interface. When users input malicious scripts into the Title field and subsequently click the preview button, the application processes this input without adequate sanitization measures. This creates an environment where javascript code or other malicious payloads can be executed in the context of other users' browser sessions, particularly those with administrative privileges. The vulnerability operates under CWE-79 which categorizes cross-site scripting flaws as weaknesses in input validation and output encoding.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to escalate privileges, steal session cookies, perform actions on behalf of users, and potentially gain full administrative control over the CMS instance. Attackers can craft malicious entries with embedded scripts that exploit the preview functionality to execute code in the browsers of other administrators or content editors who view the preview. This threat model aligns with ATT&CK technique T1566 which describes social engineering via malicious content, and T1071 which covers application layer protocol usage including web application exploitation.
Mitigation strategies for this vulnerability require immediate patching to version 3.6.2 or later where the input sanitization has been properly implemented. Organizations should also implement additional defensive measures including strict input validation at multiple layers, output encoding for all user-supplied content, and regular security testing of web application interfaces. The implementation of content security policies can provide additional protection against script execution, while monitoring for unusual preview button interactions can help detect potential exploitation attempts. Security teams should also consider implementing web application firewalls to filter suspicious input patterns and establish proper access controls to limit the impact of any successful exploitation attempts.