e107 CMS thru 2.3.3 are vulnerable to insecure deserialization in the `install.php` script. The script processes user-controlled input in the `previous_steps` POST parameter using `unserialize(base64_decode())` without validation, allowing attackers to craft malicious serialized data. This could lead to remote code execution, arbitrary file operations, or denial of service, depending on available PHP object gadgets in the codebase.
Conclusion & alert: CVE-2025-61505 is rated Low Risk (34.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.33%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
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 | 2026-06-15 | 0.55% | 0.33% | -0.22% |
| 2 | 2026-05-16 | 0.36% | 0.55% | +0.19% |
| 3 | 2026-03-20 | — | 0.36% | — |
Full EPSS history (8 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
3.9 | 2.5 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| URL | Tags |
|---|---|
| https://github.com/e107inc/e107/blob/master/install.php | Product |
| https://xancatos.org/cve202561505 | Mitigation Third Party Advisory |