What is the CVSS score of CVE-2021-42292?

CVE-2021-42292 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 31.9%.

Is CVE-2021-42292 being actively exploited?

Yes, CVE-2021-42292 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, confirming active in-the-wild exploitation. Immediate patching is required.

Is there a patch available for CVE-2021-42292?

Yes, a patch is available for CVE-2021-42292. Update the affected software to the latest version immediately.

Excel CVE-2021-42292

HIGH

2021-11-10 secure@microsoft.com

Authentication Bypass Microsoft 365 Apps Excel Office Office Long Term Servicing Channel

7.8

CVSS 3.1 · Vendor: microsoft

View

Vulnerability Assessment

Impact	CVSS score of 7.8 (HIGH). Attack characteristics: local attack vector, low complexity, no privileges required, user interaction required.
Exploit ScenarioDerived	Successful exploitation could compromise the high-severity affected system.

Act Now Prioritize within 24-48h. Why: In CISA KEV with patch available.

Exploited in the wild (CISA KEV) Patch available 31.9% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

Microsoft Excel Security Feature Bypass Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

Affected products include: Microsoft 365 Apps, Microsoft Excel, Microsoft Office, Microsoft Office Long Term Servicing Channel.

Know when Excel gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

Vendor (microsoft) PRIMARY 7.8 HIGH

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Primary rating from Vendor (microsoft) · only source for this CVE.

CVSS VectorVendor: microsoft

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Added to CISA KEV

Jul 14, 2026 - 04:22 CISA

CVE Published

Nov 10, 2021 - 01:19 cve.org

HIGH 7.8

DescriptionCVE.org

Microsoft Excel Security Feature Bypass Vulnerability

Threat Intelligence Overview

Threat Score

4.0/10

Composite threat intelligence

EPSS Score

31.9%

Top 2% exploitable

Data Quality

4 sources

Confidence: Medium

NVD

CVE.org

CISA KEV

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity HIGH

CISA KEV Yes

Public POC No

EPSS 31.9%

Patch available Yes

Active threat Yes

Deciding rule

In CISA KEV with patch available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Out-of-Cycle

Exploitation· derived

Active

System Exposure· derived

Small

Automatable· derived

Human Impact· derived

High

Priority Score

121

Low Medium High Critical

KEV: +50

EPSS: +32

CVSS: +39

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Authentication Bypass CRITICAL

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Affected Products (CPE)CVE.org

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*

cpe:2.3:a:microsoft:excel:2013:sp1:*:*:-:*:*:*

cpe:2.3:a:microsoft:excel:2013:sp1:*:*:rt:*:*:*

cpe:2.3:a:microsoft:office:2013:sp1:*:*:-:*:*:*

cpe:2.3:a:microsoft:office:2013:sp1:*:*:rt:*:*:*

cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:*:*

cpe:2.3:a:microsoft:office:2019:*:*:*:*:-:*:*

cpe:2.3:a:microsoft:office:2019:*:*:*:*:macos:*:*

cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:*:*

cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*

More in Excel

View all

CVE-2015-0097 CRITICAL Emergency POC

9.3 Mar 11

Microsoft Excel 2007 SP3, PowerPoint 2007 SP3, Word 2007 SP3, Excel 2010 SP2, PowerPoint 2010 SP2, and Word 2010 SP2 all

CVE-2015-2523 CRITICAL Emergency POC

9.3 Sep 09

Microsoft Excel 2007 SP3, Excel 2010 SP2, Excel 2013 SP1, Excel 2013 RT SP1, Excel for Mac 2011 and 2016, Office Compati

CVE-2013-1315 CRITICAL Act Now POC

9.3 Sep 11

Microsoft SharePoint Server 2007 SP3, 2010 SP1 and SP2, and 2013; Office Web Apps 2010; Excel 2003 SP3, 2007 SP3, 2010 S

CVE-2015-2521 CRITICAL Emergency POC

9.3 Sep 09

Microsoft Excel 2007 SP3, Excel 2010 SP2, Office Compatibility Pack SP3, and Excel Viewer allow remote attackers to exec

CVE-2015-2520 CRITICAL Emergency POC

9.3 Sep 09

Microsoft Excel 2007 SP3, Excel 2010 SP2, Excel for Mac 2011 and 2016, Office Compatibility Pack SP3, and Excel Viewer a

CVE-2012-2543 CRITICAL Emergency

9.3 Nov 14

Stack-based buffer overflow in Microsoft Excel 2007 SP2 and SP3 and 2010 SP1; Office 2011 for Mac; Excel Viewer; and Off

CVE-2012-1885 CRITICAL Emergency

9.3 Nov 14

Heap-based buffer overflow in Microsoft Excel 2003 SP3, 2007 SP2 and SP3, and 2010 SP1; Office 2008 and 2011 for Mac; an

CVE-2013-3889 CRITICAL Emergency

9.3 Oct 09

Microsoft Excel 2007 SP3, 2010 SP1 and SP2, 2013, and 2013 RT; Office 2007 SP3, 2010 SP1 and SP2, 2013, and 2013 RT; Off

CVE-2012-0185 CRITICAL Emergency

9.3 May 09

Heap-based buffer overflow in Microsoft Excel 2007 SP2 and SP3 and 2010 Gold and SP1, Excel Viewer, and Office Compatibi

CVE-2012-1847 CRITICAL Emergency

9.3 May 09

Microsoft Excel 2003 SP3, 2007 SP2 and SP3, and 2010 Gold and SP1; Office 2008 and 2011 for Mac; Excel Viewer; and Offic

CVE-2012-1886 CRITICAL Emergency

9.3 Nov 14

Microsoft Excel 2003 SP3, 2007 SP2 and SP3, and 2010 SP1; Excel Viewer; and Office Compatibility Pack SP2 and SP3 allow

CVE-2012-0142 CRITICAL Emergency

9.3 May 09

Microsoft Excel 2003 SP3, 2007 SP2 and SP3, and 2010 Gold and SP1; Office 2008 for Mac; Excel Viewer; and Office Compati

Same technique Authentication Bypass

View all

CVE-2015-3306 CRITICAL POC

10.0

CVE-2023-22515 CRITICAL POC

9.8

CVE-2012-4681 CRITICAL POC

9.8

CVE-2013-2465 CRITICAL POC

9.8

CVE-2011-3544 CRITICAL POC

9.8

CVE-2022-40684 CRITICAL POC

9.8

CVE-2025-61882 CRITICAL POC

9.8

CVE-2024-0012 CRITICAL POC

9.3

References

Advisories & patches

PATCH https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42292 REF https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42292 REF https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42292

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back