CVE-2026-28495

Status: AnalyzedHigh (8.8)—

GetSimple CMS is a content management system. The massiveAdmin plugin (v6.0.3) bundled with GetSimpleCMS-CE v3.3.22 allows an authenticated administrator to overwrite the gsconfig.php configuration file with arbitrary PHP code via the gsconfig editor module. The form lacks CSRF protection, enabling a remote unauthenticated attacker to exploit this via Cross-Site Request Forgery against a logged-in admin, achieving Remote Code Execution (RCE) on the web server.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Base score: 8.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.32%
Percentile among all scored CVEs: 23
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1203 Exploitation for Client Executionexecution60 %
Primary impactT1185 Browser Session Hijackingcollection55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

🛡️ ATT&CK mitigations that cover these techniques

User Training User Account Management Application Isolation and Sandboxing Exploit Protection Update Software

Affected technologies (1)

Getsimple-ce — Getsimple CMS

CWEs

CWE-352

References

https://github.com/GetSimpleCMS-CE/GetSimpleCMS-CE/security/advisories/GHSA-92wv-q2jp-qg88

Raw JSON (NVD)

Show

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