CVE-2020-0796
SMBGhost
A remote code execution vulnerability exists in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests, aka 'Windows SMBv3 Client/Server Remote Code Execution Vulnerability'.
- CVSS
- 10.0Criticalscored by CISA
- Exploited in the wild
- Yes, in CISA KEV since 10 Feb 2022CISA deadline for US federal agencies: 10 Aug 2022known use in ransomware campaignspublic exploit code
- EPSS
- 99.8%chance of exploitation in the next 30 daystop 0.1% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 12 Mar 2020analysed here 12 Nov 2026
Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)
Summary
Triage
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
Products named in our analysis
- microsoft:windows_10_1903
- microsoft:windows_10_1909
- microsoft:windows_server_1903
- microsoft:windows_server_1909
Fix and mitigation
WAF and other mitigations
Can a WAF block it? No. This is a memory-corruption bug. Generic WAF rules do not recognise the input that triggers it; only a rule written for this specific CVE can, and only if the triggering request has a recognisable shape.
Also consider: patch
Based on the weakness type only; no CVE-specific evidence yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 10 Feb 2022. Known use in ransomware campaigns.
- CISA due date
- 10 Aug 2022, the remediation deadline for US federal agencies
- CISA required action
- Apply updates per vendor instructions.
- Public exploit code
- Yes: 3 on Exploit-DB · 2 Metasploit modules · 86 GitHub proofs of concept · 1 Nuclei template
- CISA SSVC
- exploitation active, automatable yes, technical impact totalAssessed by CISA 12 Aug 2026 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
Exploit-DB
- Microsoft Windows - 'SMBGhost' Remote Code Executionremote, 2 Jun 2020
- Microsoft Windows 10 (1903/1909) - 'SMBGhost' SMB3.1.1 'SMB2_COMPRESSION_CAPABILITIES' Local Privilege Escalationlocal, 30 Mar 2020
- Microsoft Windows 10 (1903/1909) - 'SMBGhost' SMB3.1.1 'SMB2_COMPRESSION_CAPABILITIES' Buffer Overflow (PoC)dos, 14 Mar 2020
Metasploit
- exploit/windows/local/cve_2020_0796_smbghostexploit, rank good
- exploit/windows/smb/cve_2020_0796_smbghostexploit, rank average
Nuclei
- Microsoft SMBv3 - Remote Code Executiondetection template, critical
GitHub proofs of concept
- danigargu/CVE-2020-07961,358 stars
- ly4k/SMBGhost722 stars
- jamf/CVE-2020-0796-RCE-POC569 stars
- Barriuso/SMBGhost_AutomateExploitation360 stars
and 82 more repositories
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 10 Mar 2020First public exploit or proof of concept
- 12 Mar 2020Published3 days later
- 10 Feb 2022Added to CISA KEV (exploited in the wild)699 days (about 2 years) later
- 10 Aug 2022CISA remediation due date (US federal agencies)181 days (about 6 months) later
- 12 Aug 2026CISA SSVC assessment: exploitation active1,463 days (about 4 years) later
- 1 Oct 2026CVE record last updated51 days later
- 12 Nov 2026Analysed by vulneraibility.com42 days later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
| Metric | Value | What it means |
|---|---|---|
| Attack vector | NetworkReachable over the internet or any routable network. | Reachable over the internet or any routable network. |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | NoneNo victim action needed. | No victim action needed. |
| Scope | ChangedImpact crosses a security boundary into other components. | Impact crosses a security boundary into other components. |
| Confidentiality | HighTotal data disclosure possible. | Total data disclosure possible. |
| Integrity | HighComplete modification possible. | Complete modification possible. |
| Availability | HighFull outage possible. | Full outage possible. |
Common questions
Is CVE-2020-0796 being exploited?
Yes. CVE-2020-0796 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2020-0796?
CVE-2020-0796 is rated Critical with a CVSS score of 10.0. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2020-0796?
Yes. A fix has been recorded for CVE-2020-0796. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2020-0796 affect?
CVE-2020-0796 affects microsoft:windows_10_1903, microsoft:windows_10_1909, microsoft:windows_server_1903, microsoft:windows_server_1909. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
8 references in the CVE record, grouped by the tags the record gives them.
Other links (8)
- portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2020-0796
- packetstormsecurity.com /files/156731/CoronaBlue-SMBGhost-Microsoft-Windows-10-SMB-3.1.1-Proof-Of-Concep
- packetstormsecurity.com /files/156732/Microsoft-Windows-SMB-3.1.1-Remote-Code-Execution.html
- packetstormsecurity.com /files/156980/Microsoft-Windows-10-SMB-3.1.1-Local-Privilege-Escalation.html
- packetstormsecurity.com /files/157110/SMBv3-Compression-Buffer-Overflow.html
- packetstormsecurity.com /files/157901/Microsoft-Windows-SMBGhost-Remote-Code-Execution.html
Show 2 more
- packetstormsecurity.com /files/158054/SMBleed-SMBGhost-Pre-Authentication-Remote-Code-Execution-Proof-Of
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0796
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Exploit-DB: published exploits
- Metasploit Framework: exploit and scanner modules
- Nuclei templates: detection templates
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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