Threats / Microsoft / CVE-2020-0796
CVE-2020-0796
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft SMBv3 vulnerability
Remote code execution in Microsoft SMBv3 protocol allows unauthenticated attackers to execute arbitrary code on affected servers and clients through malformed requests.
Verdict
Today item, not a backlog item.
Critical vulnerability enabling direct code execution on Windows systems via network-accessible SMB service. High EPSS score and active exploitation in ransomware campaigns indicate immediate threat to unpatched infrastructure.
CISA KEV Yes · 2022-02-103Ransomware use Flagged3EPSS 0.9981 (verify live)4Exploit Weaponized · public PoC5
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
21 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-02-10), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.9981 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, SMBv3. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-119 Memory Buffer Bounds Error — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious SMBv3 request exploiting buffer overflow in protocol handling to achieve code execution without authentication.
Business
Ransomware operators gain initial network access and lateral movement capability, leading to widespread encryption and data exfiltration across enterprise environments.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I execute arbitrary code with system privileges on compromised servers to establish persistence and deploy secondary payloads.
Business
Attackers maintain long-term access for data theft, system manipulation, and deployment of additional malware across the organization.
3
Lateral reach — past segmentation narrative 3
Attacker
I propagate laterally through the network by targeting additional SMBv3 endpoints and client systems.
Business
Attack scope expands from initial compromise to critical infrastructure, backup systems, and isolated network segments, multiplying recovery costs and downtime.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05