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Microsoft Security Update Guide · Office / Microsoft 365 Apps

Microsoft Office Access Remote Code Execution Vulnerability

Microsoft · EN CVE-2026-105596 Important Action required CVSS 8.8

Published

SummaryDetailedSecurity

What does this mean?

  • Remote Code Execution. An attacker can run their own code on the system remotely. This is the most serious type: it can lead to taking over the system.
  • It can be exploited over the network (including from the internet if the service is reachable there), without an account and if a user takes part, for example by opening a link or file.
  • CVSS 8.8 out of 10: high. Microsoft rates it Important.
  • No attacks reported; Microsoft expects exploitation to be less likely.
  • What should you do? Install the security update for the version you run (or a later cumulative update):
    • Microsoft 365 Apps for Enterprise for 32-bit Systems: KBRelease Notes https://aka.ms/OfficeSecurityReleases
    • Microsoft 365 Apps for Enterprise for 64-bit Systems: KBRelease Notes https://aka.ms/OfficeSecurityReleases
    • Microsoft Office LTSC 2024 for 32-bit editions: KBRelease Notes 16.0.17932.21056
    • Microsoft Office LTSC 2024 for 64-bit editions: KBRelease Notes 16.0.17932.21056
    • Microsoft Office LTSC 2021 for 32-bit editions: KBRelease Notes 16.0.14334.20974
    • Microsoft Office LTSC 2021 for 64-bit editions: KBRelease Notes 16.0.14334.20974

Microsoft Office Access · Remote Code Execution

Heap-based buffer overflow in Microsoft Office Access allows an unauthorized attacker to execute code over a network.

Office / Microsoft 365 Apps

What kind of flaw is this?

Key facts

Released
13 okt 2026
Impact
Remote Code Execution
Max severity
Important
Weakness
CWE-122: Heap-based Buffer Overflow
CVSS 3.1
8.8 / 7.7 (base / temporal)
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Publicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely
Customer action required
Yes
Links
Microsoft Security Update Guide · CVE.org

CVSS metrics

Base score metrics
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
Temporal score metrics
Exploit Code MaturityUnproven
Remediation LevelOfficial Fix
Report ConfidenceConfirmed

Affected products and updates

ProductUpdateBuild
Microsoft 365 Apps for Enterprise for 32-bit SystemsKBRelease Noteshttps://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit SystemsKBRelease Noteshttps://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 32-bit editionsKBRelease Notes16.0.17932.21056
Microsoft Office LTSC 2024 for 64-bit editionsKBRelease Notes16.0.17932.21056
Microsoft Office LTSC 2021 for 32-bit editionsKBRelease Notes16.0.14334.20974
Microsoft Office LTSC 2021 for 64-bit editionsKBRelease Notes16.0.14334.20974

FAQ

According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?
An attacker must send a user a malicious Office file and convince them to open it.
Is the Preview Pane an attack vector for this vulnerability?
No, the Preview Pane is not an attack vector.

Revisions

VersionDateNote
113 okt 2026Information published.

This is in the weekly digest for week 42: everything that changed in Microsoft 365 this week. →

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Source: Microsoft Security Update Guide. 365Fanatic is not affiliated with Microsoft.