Detections
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Security Updates for Microsoft Office Products (September 2026)

critical Nessus Plugin ID 344286

Synopsis

The Microsoft Office Products are affected by multiple vulnerabilities.

Description

The Microsoft Office Products are missing a security update. They are, therefore, affected by multiple vulnerabilities:

 - Insufficiently protected credentials in Microsoft Office allows an unauthorized attacker to perform spoofing over a network. (CVE-2026-64918)

 - Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code over a network. (CVE-2026-69285, CVE-2026-69442, CVE-2026-78505)

 - Heap-based buffer overflow in Microsoft Office Access allows an unauthorized attacker to execute code over a network. (CVE-2026-69529, CVE-2026-69778)

 - Buffer over-read in Microsoft Office allows an unauthorized attacker to disclose information over a network. (CVE-2026-69626)

 - Integer overflow or wraparound in Microsoft Office Word allows an unauthorized attacker to disclose information over a network. (CVE-2026-69734)

 - Out-of-bounds read in Microsoft Office allows an unauthorized attacker to disclose information over a network. (CVE-2026-69739, CVE-2026-80089)

 - Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network. (CVE-2026-69764, CVE-2026-78510, CVE-2026-78526, CVE-2026-81952)

 - Buffer over-read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network. (CVE-2026-72974)

 - Numeric truncation error in Microsoft Office Word allows an unauthorized attacker to execute code over a network. (CVE-2026-78512)

 - Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network. (CVE-2026-78515)

 - Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code over a network. (CVE-2026-78518)

 - Out-of-bounds write in Microsoft Office allows an unauthorized attacker to execute code over a network. (CVE-2026-78524)

 - Out-of-bounds read in Microsoft Office Outlook allows an unauthorized attacker to disclose information over a network. (CVE-2026-80084)

 - Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to disclose information over a network. (CVE-2026-80087)

 - Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information over a network. (CVE-2026-80088)

 - Use of uninitialized resource in Microsoft Office allows an unauthorized attacker to disclose information over a network. (CVE-2026-80091)

 - Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally. (CVE-2026-81386, CVE-2026-81389, CVE-2026-81397, CVE-2026-81398, CVE-2026-81947, CVE-2026-81948, CVE-2026-81951, CVE-2026-81959, CVE-2026-81960)

 - Exposure of sensitive system information to an unauthorized control sphere in Microsoft Office Excel allows an unauthorized attacker to disclose information locally. (CVE-2026-81387, CVE-2026-81394)

 - Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally. (CVE-2026-81388, CVE-2026-81396, CVE-2026-81953)

 - Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally. (CVE-2026-81390, CVE-2026-81392, CVE-2026-81393, CVE-2026-81395, CVE-2026-81400, CVE-2026-85875)

 - Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to disclose information locally. (CVE-2026-81391, CVE-2026-81958)

 - Buffer over-read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally. (CVE-2026-81399)

 - Access of resource using incompatible type ('type confusion') in Microsoft Office Excel allows an unauthorized attacker to disclose information locally. (CVE-2026-81401)

 - Integer overflow or wraparound in Microsoft Office Excel allows an unauthorized attacker to execute code locally. (CVE-2026-81949)

 - Double free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
 (CVE-2026-81950)

 - Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
 (CVE-2026-81954)

 - Heap-based buffer overflow in Microsoft Graphics Component allows an unauthorized attacker to execute code over a network. (CVE-2026-81955)

 - Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally. (CVE-2026-81956, CVE-2026-81957)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Microsoft has released the following security updates to address this issue:
 - KB5002916
 - KB5002904
 - KB5002898
 - KB5002913
 - KB4011160

See Also

https://support.microsoft.com/en-us/help/4011160

https://support.microsoft.com/en-us/help/5002898

https://support.microsoft.com/en-us/help/5002904

https://support.microsoft.com/en-us/help/5002913

https://support.microsoft.com/en-us/help/5002916

Plugin Details

Severity: Critical

ID: 344286

File Name: smb_nt_ms26_sep_office.nasl

Version: 1.1

Type: Local

Agent: windows

Published: 9/9/2026

Updated: 9/9/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.9

Percentile: 96.6

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-78510

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS Score Source: CVE-2026-78510

Vulnerability Information

CPE: cpe:/a:microsoft:office

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Exploit Ease: No known exploits are available

Patch Publication Date: 9/8/2026

Vulnerability Publication Date: 9/8/2026

Reference Information

CVE: CVE-2026-64918, CVE-2026-69285, CVE-2026-69442, CVE-2026-69529, CVE-2026-69626, CVE-2026-69734, CVE-2026-69739, CVE-2026-69764, CVE-2026-69778, CVE-2026-72974, CVE-2026-78505, CVE-2026-78510, CVE-2026-78512, CVE-2026-78515, CVE-2026-78518, CVE-2026-78524, CVE-2026-78526, CVE-2026-80084, CVE-2026-80087, CVE-2026-80088, CVE-2026-80089, CVE-2026-80091, CVE-2026-81386, CVE-2026-81387, CVE-2026-81388, CVE-2026-81389, CVE-2026-81390, CVE-2026-81391, CVE-2026-81392, CVE-2026-81393, CVE-2026-81394, CVE-2026-81395, CVE-2026-81396, CVE-2026-81397, CVE-2026-81398, CVE-2026-81399, CVE-2026-81400, CVE-2026-81401, CVE-2026-81947, CVE-2026-81948, CVE-2026-81949, CVE-2026-81950, CVE-2026-81951, CVE-2026-81952, CVE-2026-81953, CVE-2026-81954, CVE-2026-81955, CVE-2026-81956, CVE-2026-81957, CVE-2026-81958, CVE-2026-81959, CVE-2026-81960, CVE-2026-85875

MSFT: MS26-4011160, MS26-5002898, MS26-5002904, MS26-5002913, MS26-5002916

MSKB: 4011160, 5002898, 5002904, 5002913, 5002916