User enumeration is found in in PHPJabbers Class Scheduling System v1.0. This issue occurs during password recovery, where a difference in messages could allow an attacker to determine if the user is valid or not, enabling a brute force attack with valid users.
Conclusion & alert: CVE-2023-36135 is rated Moderate Risk (43.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.47%). Mandatory action: Review affected assets and schedule remediation.
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 | 0.16% | 0.47% | +0.31% |
| 2 | 2026-04-28 | 0.10% | 0.16% | +0.06% |
| 3 | 2025-11-21 | — | 0.10% | — |
Full EPSS history (11 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| phpjabbers | class_scheduling_system | 1.0 | cpe:2.3:a:phpjabbers:class_scheduling_system:1.0:*:*:*:*:*:*:* |