CVE-2025-21479 — Windows SMB RCE¶
Key facts
CVE-2025-21479 is a Critical vulnerability: Windows SMB RCE. This entry ships a detection-only PoC. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2025-06-03), confirming active exploitation in the wild.
Actively exploited — on the CISA KEV catalog
CVE-2025-21479 is listed on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2025-06-03), confirming exploitation in the wild. Federal remediation deadline: 2025-06-24. Prioritise patching and deploy the detection and prevention rules below.
| CVE | CVE-2025-21479 |
| Severity | Critical |
| CISA KEV | Actively exploited (added 2025-06-03) |
| Detection / prevention | — |
| PoC | poc.py |
| Source | 2025/CVE-2025-21479/ |
Details¶
Overview¶
Windows SMB rce vulnerability
Details¶
- CVE ID: CVE-2025-21479
- CVSS Score: 9.8 (Critical)
- Type: RCE
- Product: Windows SMB
Usage¶
References¶
Frequently asked questions¶
What is CVE-2025-21479?¶
CVE-2025-21479 is a Critical vulnerability: Windows SMB RCE. This entry ships a detection-only PoC. It is on the CISA Known Exploited Vulnerabilities (KEV) catalog (added 2025-06-03), confirming active exploitation in the wild.
How do I detect CVE-2025-21479?¶
Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.
How do I block or mitigate CVE-2025-21479?¶
Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.
Is CVE-2025-21479 actively exploited?¶
Yes. CVE-2025-21479 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, added 2025-06-03, which means it has been exploited in the wild. CISA set a federal remediation deadline of 2025-06-24. Prioritise patching and deploy the detection and prevention rules above.
For authorized security testing and research only. See the full source and NVD record.