CVE-2021-34473Critical KEVConfirmedExploit available
MSR
MSR
Microsoft Security Response Center
The Security Update Guide is the source of truth for vulnerabilities in Microsoft products — KB article numbers, impacted builds and replacement patches. MSRC also assigns the MSRC-specific exploitability index used alongside CVSS.
Region
US
Updates
Patch Tuesday + ad-hoc
License
Proprietary
Microsoft's Security Update Guide, covering Windows, Office, Azure, SQL Server, Exchange and other first-party products.
https://msrc.microsoft.com/update-guide →Share link
Anyone with the link can open this vulnerability.
Microsoft Exchange Server Remote Code Execution Vulnerability
CVSS
9.8
Critical
EPSS
1.00
p100
Published
2021-01-01
Updated
2021-11-03
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
Tags · CWE
KEVPre-auth
CWE-918
CWE-918BaseIncomplete
Server-Side Request Forgery (SSRF)
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
https://cwe.mitre.org/data/definitions/918.html →Open in CWE collection →CAPEC-664
CAPEC-664StandardStable
Server Side Request Forgery
https://capec.mitre.org/data/definitions/664.html →Open in CAPEC collection →
Affected products
Exchange_server
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Timeline
2021-01-01
Published
2021-11-03
Added to KEV
2021-11-03
Updated
CVSS 3.1 breakdown
Attack Vector
AV: N
Network (N)
Attack Complexity
AC: L
Low (L)
Privileges Required
PR: N
None (N)
User Interaction
UI: N
None (N)
Scope
S: U
Unchanged (U)
Confidentiality Impact
C: H
High (H)
Integrity Impact
I: H
High (H)
Availability Impact
A: H
High (H)
Exploit indicators
EPSS
1.000 · p100
Known exploited (KEV)
Yes
Known exploits — Сканер-ВС
CVE-2021-34473
cisa · https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Affected software
| Product | Vendor | Status |
|---|---|---|
| exchange_server | * | Exploited |
| Windows | Microsoft | Exploited |
| Windows | Microsoft | Exploited |
| Windows | Microsoft | Exploited |
| Windows | Microsoft | Exploited |
| Windows | Microsoft | Exploited |
Source databases
MSR
MSR
Microsoft Security Response Center
The Security Update Guide is the source of truth for vulnerabilities in Microsoft products — KB article numbers, impacted builds and replacement patches. MSRC also assigns the MSRC-specific exploitability index used alongside CVSS.
Region
US
Updates
Patch Tuesday + ad-hoc
License
Proprietary
Microsoft's Security Update Guide, covering Windows, Office, Azure, SQL Server, Exchange and other first-party products.
https://msrc.microsoft.com/update-guide →CVE
CVE
National Vulnerability Database
NVD is the U.S. government repository of standards-based vulnerability management data, built on top of the MITRE CVE list. Every record includes CPE applicability statements, CVSS v2 and v3.x base scores, CWE mappings and cross-references to advisories.
Region
US
Updates
15 min
License
Public Domain
Comprehensive catalog of publicly disclosed vulnerabilities with CPE matches, CVSS scoring and reference URLs. De-facto standard for cross-vendor correlation.
https://nvd.nist.gov →Related vulnerabilities