CVE-2021-40219
HighCVSS 8.8Exploitation Probability (EPSS)
High risk87th percentile - higher than 87% of all known CVEs
Summary
Bolt CMS version 4.2 and earlier is vulnerable to Remote Code Execution. Unsafe theme rendering allows an authenticated attacker to edit the theme and inject server-side template injection, leading to remote code execution.
Risk Assessment
The risk for the organization is the potential takeover of the server by an authenticated user, which could lead to data theft, content modification, or further attacks on the infrastructure.
Recommendation
It is recommended to immediately upgrade Bolt CMS to a version newer than 4.2 and restrict theme editing permissions to trusted administrators only.
Other vulnerabilities in Bolt CMS
See all- CVE-2022-36532High
Bolt CMS version 5.1.12 and below contains a vulnerability that allows an authenticated user with ROLE_EDITOR privileges to upload and rename a malicious file, leading to remote code execution.
- CVE-2026-71291High
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex, then compiles and renders the raw value without sandboxing.
- CVE-2026-11511Low
In Bolt CMS up to version 3.7.5, in the TextType.php file of the HTML Attribute Handler component, manipulation of the style argument leads to HTML injection. The attack is remote, exploit is public. The GitHub repository is archived and read-only, and the product is no longer supported.
- CVE-2026-39229Medium
Bolt CMS up to version 3.7.0 contains an SQL injection vulnerability in the 'order' parameter of content listing pages. An authenticated attacker with low privileges can exploit this via the OrderDirective component, allowing extraction of sensitive information.
Original NVD description (English source)
Bolt CMS <= 4.2 is vulnerable to Remote Code Execution. Unsafe theme rendering allows an authenticated attacker to edit theme to inject server-side template injection that leads to remote code execution.