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CVE-2021-36394

Status: ModifiedCritical (9.8)—PoC
Severity9.8Critical · CVSS 3.1
Exploitation probability7.03 %higher than 94% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailableProof of concept on GitHub (unverified)

In Moodle, a remote code execution risk was identified in the Shibboleth authentication plugin.

CVSS

Base score
9.8
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
7.03 %
Percentile among all scored CVEs
94
Score date
10/28/2026

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).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (1)

Moodle — Moodle

CWEs

References

Show 2 references

Raw JSON (NVD)

Show
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