CVE-2026-78507
published 2026-09-08CVE-2026-78507: Use after free in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
PriorityP356high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.59%
46.5th percentile
Use after free in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_365_apps_for_enterprise | >= 16.0.1 < 16.0.20326.20138 | 16.0.20326.20138 |
| microsoft | microsoft_office_2019 | >= 19.0.0 < 16.0.10417.20207 | 16.0.10417.20207 |
| microsoft | microsoft_office_365_for_mac | — | — |
| microsoft | microsoft_office_ltsc_2021 | >= 16.0.1 < 16.0.14334.20906 | 16.0.14334.20906 |
| microsoft | microsoft_office_ltsc_2024 | >= 16.0.0 < 16.0.17932.20976 | 16.0.17932.20976 |
| microsoft | microsoft_office_ltsc_for_mac_2021 | — | — |
| microsoft | microsoft_office_ltsc_for_mac_2024 | — | — |
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VulDB
Microsoft Office LTSC for Mac 2024 use after free (Nessus ID 344562)
vuldb·2026-09-10·CVSS 8.8
CVE-2026-78507 [HIGH] Microsoft Office LTSC for Mac 2024 use after free (Nessus ID 344562)
A vulnerability was found in Microsoft 365 Apps for Enterprise, Office 2019, Office 365 for Mac, Office LTSC 2021, Office LTSC 2024, Office LTSC for Mac 2021 and Office LTSC for Mac 2024. It has been declared as problematic. This vulnerability affects unknown code. The manipulation results in use after free.
This vulnerability is cataloged as CVE-2026-78507. The attack may be launched remotely. There is no exploit available.
It is best practice to apply a patch to resolve this issue.
GHSA
Use after free in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
ghsa_unreviewed·2026-09-08
CVE-2026-78507 [HIGH] CWE-416 Use after free in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
Use after free in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
No detection rules found.
No public exploits indexed.
Sans Isc
September 2026 Microsoft Patch Tuesday, (Tue, Sep 8th)
blogs_sans_isc·2026-09-08·CVSS 7.8
CVE-2026-81963 [HIGH] September 2026 Microsoft Patch Tuesday, (Tue, Sep 8th)
September 2026 Microsoft Patch Tuesday
Published: 2026-09-08. Last Updated: 2026-09-08 19:20:30 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
This month, Microsoft released patches for a record-breaking 973 vulnerabilities, including 113 rated critical. It is by far the largest Patch Tuesday to date, well ahead of the previous high of 664 set in July 2026. Two vulnerabilities are listed as exploited in the wild, while none were publicly disclosed before Patch Tuesday. Notable fixes include Windows privilege escalation and critical RCEs in Skype for Business, MSMQ and RRAS.
A few vulnerabilities worth mentioning:
Windows Update Stack Elevation of Privilege Vulnerability (CVE-2026-81963)
Microsoft reports that CVE-2026-81963 is being exploited, though it was not publicly disclosed b
Rapid7
Patch Tuesday - September 2026
blogs_rapid7·2026-09-08·CVSS 7.8
CVE-2026-85880 [HIGH] Patch Tuesday - September 2026
Microsoft is publishing 974 own-product vulnerabilities on September 2026 Patch Tuesday , including 723 vulnerabilities in Windows. Along with Microsoft fixes for 25 non-Microsoft CVEs, that brings the total number of vulnerabilities on the table today to 999. Whether this is the biggest Patch Tuesday ever depends on how we count, but this is by far the most CVEs that Microsoft has ever published in a single day. As Rapid7 noted last month, there is no reason to suppose that Patch Tuesday will ever return to the lower volumes we saw prior to 2026. Microsoft is aware of exploitation in the wild for two of the vulnerabilities published today.
## Windows ALPC: zero-day EoP
The eternal game of elevation of privilege whack-a-mole between Microsoft and attackers continues. This month, the batt
2026-09-08
Published