CVE-2020-0646

Exp

A remote code execution vulnerability exists when the Microsoft .NET Framework fails to validate input properly, aka '.NET Framework Remote Code Execution Injection Vulnerability'.

Published: 2020-01-14 Last update: 2025-10-29 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-0646 is rated Critical Active Threat (99.6/100): CVSS Critical severity, with high exploitation likelihood (EPSS 93.86%, 100th percentile). CISA KEV confirms active exploitation (added 2021-11-03) affecting Microsoft / .NET Framework. a weakness (CWE-91) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2020-0646

Name: Microsoft .NET Framework Remote Code Execution Vulnerability · CISA KEV detail

Exploit added: 2021-11-03

Action due: 2022-05-03

Required action: Apply updates per vendor instructions.

Public exploit references (Exploit-DB) for CVE-2020-0646

EDB-ID Source Kind Published Link
48275 exploit_db edb 2020-03-31 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-0646

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 2025-11-22 93.37% 93.86% +0.50%
2 2025-11-21 92.68% 93.37% +0.69%
3 2025-11-18 — 92.68% —

Full EPSS history (44 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-0646

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 10.0 10.0 [email protected]

Weakness enumeration for CVE-2020-0646

Affected software / configurations for CVE-2020-0646

Vendor Product Version Raw CPE
microsoft .net_framework 3.0 cpe:2.3:a:microsoft:.net_framework:3.0:sp2:*:*:*:*:*:*
microsoft .net_framework 3.5 cpe:2.3:a:microsoft:.net_framework:3.5:*:*:*:*:*:*:*
microsoft .net_framework 4.6.2 cpe:2.3:a:microsoft:.net_framework:4.6.2:*:*:*:*:*:*:*
microsoft .net_framework 4.7 cpe:2.3:a:microsoft:.net_framework:4.7:*:*:*:*:*:*:*
microsoft .net_framework 4.7.1 cpe:2.3:a:microsoft:.net_framework:4.7.1:*:*:*:*:*:*:*
microsoft .net_framework 4.7.2 cpe:2.3:a:microsoft:.net_framework:4.7.2:*:*:*:*:*:*:*
microsoft .net_framework 4.8 cpe:2.3:a:microsoft:.net_framework:4.8:*:*:*:*:*:*:*
microsoft .net_framework 3.5.1 cpe:2.3:a:microsoft:.net_framework:3.5.1:*:*:*:*:*:*:*
microsoft .net_framework 4.5.2 cpe:2.3:a:microsoft:.net_framework:4.5.2:*:*:*:*:*:*:*
microsoft .net_framework 4.6 cpe:2.3:a:microsoft:.net_framework:4.6:*:*:*:*:*:*:*
microsoft .net_framework 4.6.1 cpe:2.3:a:microsoft:.net_framework:4.6.1:*:*:*:*:*:*:*

References for CVE-2020-0646

cvelogic Threat Intelligence