CVE-2026-78510
Microsoft Outlook and Word Remote Code Execution Vulnerability
Description
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
INFO
Published Date :
Sept. 8, 2026, 6:20 p.m.
Last Modified :
Sept. 25, 2026, 10:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-78510
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Install the September 2026 security updates.
- Verify that all patches are successfully applied.
- Restart affected systems if required.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-78510.
| URL | Resource |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78510 | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-78510 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-78510
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-78510 vulnerability anywhere in the article.
-
CrowdStrike.com
September 2026 Patch Tuesday: Two Exploited Zero-Days and 113 Critical Vulnerabilities Among 972 CVEs
Microsoft has addressed 972 vulnerabilities in its September 2026 security update release, over double the number of CVEs released in August, and a new Patch Tuesday record. This month's patches inclu ... Read more
The following table lists the changes that have been made to the
CVE-2026-78510 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Sep. 25, 2026
Action Type Old Value New Value Changed Description A remote code execution vulnerability exists when Microsoft Office improperly validates input before loading dynamic link library (DLL) files. An attacker who successfully exploited this vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. To exploit the vulnerability, an attacker must first convince a user to open a specially crafted Office document. The updates address the vulnerability by correcting how Office validates input before loading DLL files. Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally. Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Removed CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
CVE Modified by [email protected]
Sep. 24, 2026
Action Type Old Value New Value Changed Description Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code over a network. A remote code execution vulnerability exists when Microsoft Office improperly validates input before loading dynamic link library (DLL) files. An attacker who successfully exploited this vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. To exploit the vulnerability, an attacker must first convince a user to open a specially crafted Office document. The updates address the vulnerability by correcting how Office validates input before loading DLL files. -
CVE Modified by [email protected]
Sep. 21, 2026
Action Type Old Value New Value Changed Description Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network. Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code over a network. -
CVE Modified by [email protected]
Sep. 17, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/78xxx/CVE-2026-78510.json">CVE-2026-78510</a> -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 09, 2026
Action Type Old Value New Value Changed SSVC {'id': 'CVE-2026-78510', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-04T00:00:00+00:00'} {'id': 'CVE-2026-78510', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-09T04:21:18.735957Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 09, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-78510', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-04T00:00:00+00:00'} -
Initial Analysis by [email protected]
Sep. 08, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:* *cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:* *cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:* *cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:* *cpe:2.3:a:microsoft:office_2016:-:*:*:*:-:*:x64:* *cpe:2.3:a:microsoft:office_2016:-:*:*:*:-:*:x86:* *cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:* *cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:* *cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:* *cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:* *cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:* *cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:* *cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:* Added Reference Type Microsoft Corporation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78510 Types: Patch, Vendor Advisory -
CVE Modified by [email protected]
Sep. 08, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/78xxx/CVE-2026-78510.json">CVE-2026-78510</a> -
New CVE Received by [email protected]
Sep. 08, 2026
Action Type Old Value New Value Added Description Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-122 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/78xxx/CVE-2026-78510.json">CVE-2026-78510</a> Added Reference https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78510