What is CVE-2026-39387?

CVE-2026-39387 is a high-severity vulnerability in Boidcms, classified under PHP Remote File Inclusion. CVSS score: 7.2/10. Published 2026-04-14.

How severe is CVE-2026-39387?

High severity. CVSS v3 base score is 7.2 out of 10.

Is CVE-2026-39387 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Boidcms

CVE-2026-39387

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 modified 2026-07-24.

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (55.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 55.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.008 · change: +0.001

Affected products

Boidcms — versions < 2.1.3

Weakness classification (CWE)

CWE-98 — PHP Remote File Inclusion

Public proof-of-concept exploits

xp1tr/CVE-2026-39387

References

github.com/BoidCMS/BoidCMS/security/advisories/GHSA-45xp-xw54-6cv6 (Exploit, Mitigation, Vendor Advisory)
github.com/BoidCMS/BoidCMS/releases/tag/v2.1.3 (Product, Release Notes)

Frequently asked questions

What is CVE-2026-39387?: CVE-2026-39387 is a high-severity vulnerability in Boidcms, classified under PHP Remote File Inclusion. CVSS score: 7.2/10. Published 2026-04-14.
How severe is CVE-2026-39387?: High severity. CVSS v3 base score is 7.2 out of 10.
Is CVE-2026-39387 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.