NVD - CVE-2021-34523 (original) (raw)
Metrics
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:
NIST: NVD
NVD assessment not yet provided.
CVSS 3.x Severity and Vector Strings:
NIST: NVD
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA: Microsoft Corporation
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
CVSS 2.0 Severity and Vector Strings:
NIST: NVD
Vector: (AV:N/AC:L/Au:N/C:P/I:P/A:P)
References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to [email protected].
| URL | Source(s) | Tag(s) |
|---|---|---|
| http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html | CVE, Microsoft Corporation | Exploit Third Party Advisory VDB Entry |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34523 | CVE, Microsoft Corporation | Patch Vendor Advisory |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-34523 | CISA-ADP | US Government Resource |
| https://www.zerodayinitiative.com/advisories/ZDI-21-822/ | CVE, Microsoft Corporation | Third Party Advisory VDB Entry |
This CVE is in CISA's Known Exploited Vulnerabilities Catalog
Reference CISA's BOD 22-01 and Known Exploited Vulnerabilities Catalog for further guidance and requirements.
| Vulnerability Name | Date Added | Due Date | Required Action |
|---|---|---|---|
| Microsoft Exchange Server Privilege Escalation Vulnerability | 11/03/2021 | 11/17/2021 | Apply updates per vendor instructions. |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| NVD-CWE-noinfo | Insufficient Information | NIST |
Known Affected Software Configurations Switch to CPE 2.2
Change History
14 change records found show changes
Modified Analysis by NIST 10/30/2025 3:13:30 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference Type | CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field\_cve=CVE-2021-34523 Types: US Government Resource |
CVE Modified by CISA-ADP 10/21/2025 8:17:38 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference | https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field\_cve=CVE-2021-34523 |
CVE Modified by CISA-ADP 10/21/2025 4🔞38 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Removed | Reference | https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field\_cve=CVE-2021-34523 |
CVE Modified by CISA-ADP 10/21/2025 3:19:08 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference | https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field\_cve=CVE-2021-34523 |
Modified Analysis by NIST 3/07/2025 3:16:42 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | CWE | NVD-CWE-noinfo | |
| Removed | CWE | CWE-287 |
CVE Modified by CVE 11/21/2024 1:10:35 AM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference | http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html | |
| Added | Reference | https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34523 | |
| Added | Reference | https://www.zerodayinitiative.com/advisories/ZDI-21-822/ |
CVE Modified by Microsoft Corporation 5/14/2024 5:13:44 AM
| Action | Type | Old Value | New Value |
|---|
Modified Analysis by NIST 2/13/2024 12:20:51 PM
| Action | Type | Old Value | New Value |
|---|
CVE Modified by Microsoft Corporation 12/28/2023 6:15:41 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Changed | Description | Microsoft Exchange Server Elevation of Privilege Vulnerability This CVE ID is unique from CVE-2021-33768, CVE-2021-34470. | Microsoft Exchange Server Elevation of Privilege Vulnerability |
| Added | CVSS V3.1 | Microsoft Corporation AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N |
CWE Remap by NIST 7/12/2022 1:42:04 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Changed | CWE | CWE-269 | CWE-287 |
Modified Analysis by NIST 9/21/2021 1:34:36 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Changed | Reference Type | http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html No Types Assigned | http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html Exploit, Third Party Advisory, VDB Entry |
CVE Modified by Microsoft Corporation 8/20/2021 2:15:07 PM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference | http://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html [No Types Assigned] |
Initial Analysis by NIST 7/22/2021 10:41:49 AM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | CVSS V3.1 | NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | |
| Added | CVSS V2 | NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P) | |
| Added | CWE | NIST CWE-269 | |
| Added | CPE Configuration | OR *cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:* *cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_19:*:*:*:*:*:* *cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_20:*:*:*:*:*:* *cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_8:*:*:*:*:*:* *cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_9:*:*:*:*:*:* | |
| Changed | Reference Type | https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34523 No Types Assigned | https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34523 Patch, Vendor Advisory |
| Changed | Reference Type | https://www.zerodayinitiative.com/advisories/ZDI-21-822/ No Types Assigned | https://www.zerodayinitiative.com/advisories/ZDI-21-822/ Third Party Advisory, VDB Entry |
CVE Modified by Microsoft Corporation 7/19/2021 6:15:08 AM
| Action | Type | Old Value | New Value |
|---|---|---|---|
| Added | Reference | https://www.zerodayinitiative.com/advisories/ZDI-21-822/ [No Types Assigned] |