CVE-2026-39393

HIGHNVD 8.18.1
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under NVD CVSS v3. EPSS exploit probability: 0.1%, top 83% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Elevated
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to 0.31.4.0, the install route guard in ci4ms relies solely on a volatile cache check (cache('settings')) combined with .env file existence to block post-installation access to the setup wizard. When the database is temporarily unreachable during a cache miss (TTL expiry or admin-triggered cache clear), the guard fails open, allowing an unauthenticated attacker to overwrite the .env file with attacker-controlled database credentials, achieving full application takeover. This vulnerability is fixed in 0.31.4.0.

CVSS v3
8.1
EG Score
8.1(medium)
EPSS
34.0%
KEV
Not listed

Published

April 8, 2026

Last Modified

April 16, 2026

Advisory Details (1)

Auto-updated Jun 10, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Post-Installation Re-entry via Cache-Dependent Install Guard Bypass in ci4ms · Advisory · ci4-cms-erp/ci4ms · GitHub

https://github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-8rh5-4mvx-xj7j

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Frequently asked(5)

What is CVE-2026-39393?
CVE-2026-39393 is a high vulnerability published on April 8, 2026. CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to 0.31.4.0, the install route guard in ci4ms relies solely on a volatile cache check (cache('settings')) combined with .env file existence to block…
When was CVE-2026-39393 disclosed?
CVE-2026-39393 was first published in the National Vulnerability Database on April 8, 2026, with the most recent update on April 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-39393 actively exploited?
CVE-2026-39393 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 34.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-39393?
CVE-2026-39393 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-39393?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-39393, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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