CVE-2026-45139
MEDIUMCVE-2026-45139 is a medium-severity (CVSS 6.5) CWE-73 vulnerability in ci4-cms-erp/ci4ms. O3 Security confirms whether CVE-2026-45139 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
CI4MS Fileeditor allows deletion and rename of critical application files due to missing extension allowlist on destructive operations
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-45139.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-45139 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 0 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
ci4-cms-erp/ci4msReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
CI4MS is a CodeIgniter 4-based content management system skeleton. Prior to version 0.31.9.0, the Fileeditor module enforces an extension allowlist (['css','js','html','txt','json','sql','md']) on content-write operations (saveFile, createFile), but two destructive endpoints — deleteFileOrFolder and renameFile — never validate the extension of the source path. A backend user with file-editor permissions can therefore unlink or rename any file inside the project root that is not explicitly listed in the small $hiddenItems blocklist. Critical framework files such as app/Config/Routes.php, app/Config/App.php, app/Config/Database.php, app/Config/Filters.php, public/index.php, and public/.htaccess all live outside that blocklist and can be destroyed, producing a persistent denial of service that requires filesystem-level redeployment to recover. Version 0.31.9.0 patches the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | ci4-cms-erp/ci4ms | all versions | 0.31.9.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ci4-cms-erp/ci4ms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update ci4-cms-erp/ci4ms to 0.31.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45139 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-45139 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-45139. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-45139 in your dependencies?
O3 detects CVE-2026-45139 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.