CVE-2021-27057: Microsoft Office Graph Uninitialized Variable Remote Code Execution Vulnerability

Published Mar 9, 2021
·
Updated

Microsoft Office Remote Code Execution Vulnerability

Other sources

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Microsoft Office. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the Graph COM object. The issue results from the lack of proper initialization of memory prior to accessing it. An attacker can leverage this vulnerability to execute code in the context of the current process.

ZDI

Affected Software

35 affected componentsFixes available
Microsoft Office
Microsoft 365 Apps
Microsoft Excel=2010-sp2
Microsoft Excel=2013-sp1
Microsoft Excel=2013-sp1
Microsoft Excel=2016
Microsoft Office=2010-sp2
Microsoft Office=2013-sp1
Microsoft Office=2013-sp1
Microsoft Office=2016
Microsoft Office=2019
Microsoft Office Macos=2019
Microsoft Office Online Server
Microsoft Office Web Apps=2013-sp1
Microsoft Office 2013<15.0.5327.1000
15.0.5327.1000
Microsoft Office 2013<15.0.5327.1000
15.0.5327.1000
Microsoft Office Web Apps 2013<15.0.5327.1000
15.0.5327.1000
Microsoft Office 2013 RT
Microsoft Office 2010<14.0.7266.5000
14.0.7266.5000
Microsoft Excel 2013<15.0.5327.1000
15.0.5327.1000
Microsoft Excel 2010<14.0.7266.5000
14.0.7266.5000
Microsoft Excel 2013 RT
Microsoft Office 2010<14.0.7266.5000
14.0.7266.5000
Microsoft Excel 2010<14.0.7266.5000
14.0.7266.5000
Microsoft Excel 2016<16.0.5134.1000
16.0.5134.1000
Microsoft Office 2016<16.0.5134.1000
16.0.5134.1000
Microsoft Excel 2013<15.0.5327.1000
15.0.5327.1000
Microsoft 365 Apps for Enterprise<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2016<16.0.5134.1000
16.0.5134.1000
Microsoft Office 2019 for Mac
Microsoft Excel 2016<16.0.5134.1000
16.0.5134.1000
Microsoft Office 2019 for 32-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases
Microsoft Office Online Server<16.0.10372.20000
16.0.10372.20000
Microsoft Office 2019 for 64-bit editions<https://aka.ms/OfficeSecurityReleases
https://aka.ms/OfficeSecurityReleases

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.0.5327.1000Patch KB4493203
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.0.5327.1000Patch KB4493234
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 14.0.7266.5000Patch KB4493214
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.0.5327.1000Patch KB4493239
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 14.0.7266.5000Patch KB4504707
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4493203
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch KB4493239
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.5134.1000Patch KB4493200
  9. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.5134.1000Patch KB4493233
  10. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in https://aka.ms/OfficeSecurityReleases
  11. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.0.10372.20000Patch KB4493229

Event History

Mar 9, 2021
CVE Published
via Microsoft·04:00 PM
Data Sourced
via Microsoft·04:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·04:00 PM
Affected Software
Updated
via Microsoft·04:00 PM
Description
Mar 11, 2021
CVE Published
via MITRE·03:48 PM
Data Sourced
via MITRE·03:48 PM
DescriptionSeverity
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityAffected Software
Mar 17, 2021
Advisory Published
via ZDI·12:00 AM
Data Sourced
via ZDI·12:00 AM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is CVE-2021-27057?

CVE-2021-27057 is a vulnerability that allows remote attackers to execute arbitrary code on affected installations of Microsoft Office.

2

How can remote attackers exploit CVE-2021-27057?

Remote attackers can exploit CVE-2021-27057 by having the target visit a malicious page or open a malicious file.

3

What is the severity of CVE-2021-27057?

CVE-2021-27057 has a severity score of 7.8 out of 10, indicating a high severity.

4

Which versions of Microsoft Office are affected by CVE-2021-27057?

CVE-2021-27057 affects various versions of Microsoft Office, including Office Online Server, Office 2019, Office 2016, Office 2013, Excel 2013, and Excel 2010.

5

How can I fix CVE-2021-27057?

To fix CVE-2021-27057, update your affected installations of Microsoft Office by applying the patches provided by Microsoft.

Contact

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