CVE-2021-34478
published 2021-08-12CVE-2021-34478: Microsoft Office Remote Code Execution Vulnerability
PriorityP355high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
EPSS
54.38%
98.9th percentile
Microsoft Office Remote Code Execution Vulnerability
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_365_apps_for_enterprise | >= 16.0.1 < https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases |
| microsoft | microsoft_office_2019 | >= 19.0.0 < https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases |
| microsoft | office | — | — |
| msrc | microsoft_365_apps_for_enterprise_for_32-bit_systems | — | — |
| msrc | microsoft_365_apps_for_enterprise_for_64-bit_systems | — | — |
| msrc | microsoft_office_2019_for_32-bit_editions | — | — |
| msrc | microsoft_office_2019_for_64-bit_editions | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Preview Pane is NOT an attack vector; focus detection on file open/execution events rather than preview activity ↗
- →User interaction required — monitor for users being socially engineered into opening/running malicious Office files (spearphishing attachment scenarios) ↗
- ·Exploitation assessed as 'Less Likely' for both latest and older software releases; no public exploit or in-the-wild exploitation confirmed at time of advisory ↗
- ·Remediation is delivered via Click-to-Run update channel; ensure Click-to-Run Office installations have received the patch rather than relying solely on MSI/Windows Update patching pipelines ↗
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
vendor_msrc7.8HIGH
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Microsoft
Microsoft Office Remote Code Execution Vulnerability
vendor_msrc·2021-08-10·CVSS 7.8
CVE-2021-34478 [HIGH] Microsoft Office Remote Code Execution Vulnerability
Microsoft Office Remote Code Execution Vulnerability
FAQ: Is the Preview Pane an attack vector for this vulnerability?
No, the Preview Pane is not an attack vector.
FAQ: According to the CVSS score, user interaction is required to exploit this vulnerability. What kind of user interaction is required?
A user needs to be tricked into running malicious files.
Microsoft Office: Microsoft Office
Microsoft: Microsoft
Impact: Remote Code Execution
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely;Older Software Release:Exploitation Less Likely;DOS:N/A
Remediation: Click to Run
GHSA
GHSA-j59g-pjr7-6mxg: Microsoft Office Remote Code Execution Vulnerability
ghsa_unreviewed·2022-05-24
CVE-2021-34478 [HIGH] GHSA-j59g-pjr7-6mxg: Microsoft Office Remote Code Execution Vulnerability
Microsoft Office Remote Code Execution Vulnerability
No detection rules found.
No public exploits indexed.
Qualys
Microsoft and Adobe Patch Tuesday (August 2021) – Microsoft 51 Vulnerabilities with 7 Critical, Adobe 29 Vulnerabilities
blogs_qualys·2021-08-10·CVSS 7.0
CVE-2021-36942 [HIGH] Microsoft and Adobe Patch Tuesday (August 2021) – Microsoft 51 Vulnerabilities with 7 Critical, Adobe 29 Vulnerabilities
## Microsoft Patch Tuesday – August 2021
Microsoft patched 51 vulnerabilities in their August 2021 Patch Tuesday release, and 7 of them are rated as critical severity. Three 0-day vulnerability patches were included in the release.
## Critical Microsoft Vulnerabilities Patched
CVE-2021-36942 – Windows LSA Spoofing Vulnerability
An unauthenticated attacker could call a method on the LSARPC interface and coerce the domain controller to authenticate against another server using NTLM. A malicious user can use this attack to take complete control over windows domain Per Microsoft, this vulnerability affects all servers, but domain controllers should be prioritized in terms of applying security updates.
CVE-2021-34481 – Windows Print Spooler Remote Code Execution Vulnerability
A remote cod
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2021-08-12
Published