BoidCMS is an open-source, PHP-based flat-file CMS for building simple websites and blogs, using JSON as its database. Versions prior to 2.1.3 are vulnerable to a critical Local File Inclusion (LFI) attack via the tpl parameter, which can lead to Remote Code Execution (RCE).The application fails to sanitize the tpl (template) parameter during page creation and updates. This parameter is passed directly to a require_once() statement without path validation. An authenticated administrator can exploit this by injecting path traversal sequences (../) into the tpl value to escape the intended theme directory and include arbitrary files — specifically, files from the server's media/ directory. When combined with the file upload functionality, this becomes a full RCE chain: an attacker can first upload a file with embedded PHP code (e.g., disguised as image data), then use the path traversal vulnerability to include that file via require_once(), executing the embedded code with web server privileges. This issue has been fixed in version 2.1.3.
Conclusion & alert: CVE-2026-39387 is rated Exploit Available (56.4/100): CVSS High severity, with low exploitation likelihood (EPSS 0.15%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-26 | 0.11% | 0.15% | +0.04% |
| 2 | 2026-05-22 | 0.37% | 0.11% | -0.25% |
| 3 | 2026-05-16 | — | 0.37% | — |
Full EPSS history (5 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.2 | 3.1 | HIGH |
|
1.2 | 5.9 | [email protected] |
| URL | Tags |
|---|---|
| https://github.com/BoidCMS/BoidCMS/releases/tag/v2.1.3 | Product Release Notes |
| https://github.com/BoidCMS/BoidCMS/security/advisories/GHSA-45xp-xw54-6cv6 | Exploit Mitigation Vendor Advisory |