CVE-2026-39387 | BoidCMS: Local File Inclusion (LFI) leads to Remote Code Execution (RCE) via tpl parameter

Exp

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.

Published: 2026-04-14 Last update: 2026-04-23 Assigner: [email protected] Source: [email protected]

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.

Public exploit references (Exploit-DB) for CVE-2026-39387

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-39387

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)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-39387

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2 5.9 [email protected]

Weakness enumeration for CVE-2026-39387

Affected software / configurations for CVE-2026-39387

Vendor Product Version Raw CPE
boidcms boidcms < 2.1.3 cpe:2.3:a:boidcms:boidcms:*:*:*:*:*:*:*:*

References for CVE-2026-39387

cvelogic Threat Intelligence