GHSA-2563-fp9c-mgm8 · Severity: critical · Ecosystem: composer — Moodle Session Fixation vulnerability
In Moodle, a remote code execution risk was identified in the Shibboleth authentication plugin.
Conclusion & alert: CVE-2021-36394 is rated High Risk (67.3/100): CVSS Critical severity, with high exploitation likelihood (EPSS 7.03%, 93th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize 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 | 11.65% | 7.03% | -4.61% |
| 2 | 2026-03-08 | 20.55% | 11.65% | -8.90% |
| 3 | 2026-03-07 | — | 20.55% | — |
Full EPSS history (32 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.1 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
GHSA-2563-fp9c-mgm8 · Severity: critical · Ecosystem: composer — Moodle Session Fixation vulnerability
| vendor | priority | summary | link |
|---|---|---|---|
ubuntu
|
medium | CVE-2021-36394 medium priority: Ubuntu including 1 source packages (moodle), 7 status rows across 7 suites (bionic, focal, jammy, kinetic, trusty, upstream, xenial): DNE 3, needs-triage 3, ignored 1. | https://ubuntu.com/security/CVE-2021-36394 |
| URL | Tags |
|---|---|
| https://moodle.org/mod/forum/discuss.php?d=424799 | Patch Vendor Advisory |