CVE-2026-66807
published 2026-08-11CVE-2026-66807: Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
PriorityP347high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
EPSS
0.35%
28.0th percentile
Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Affected
9 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 | microsoft_office_365_for_mac | >= 1.0.0 < 16.112.26081010 | 16.112.26081010 |
| microsoft | microsoft_office_ltsc_2021 | >= 16.0.1 < https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases |
| microsoft | microsoft_office_ltsc_2024 | >= 16.0.0 < https://aka.ms/OfficeSecurityReleases | https://aka.ms/OfficeSecurityReleases |
| microsoft | microsoft_office_ltsc_for_mac_2021 | >= 16.0.1 < 16.112.26081010 | 16.112.26081010 |
| microsoft | microsoft_office_ltsc_for_mac_2024 | >= 16.0.0 < 16.112.26081010 | 16.112.26081010 |
| multicluster-engine | console-mce-rhel9 | — | — |
| rhacm2 | console-rhel9 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat7.8HIGH
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Red Hat
console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
vendor_redhat·2026-08-14·CVSS 7.8
CVE-2026-66807 [HIGH] CWE-79 console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
A flaw was found in console. The `getCodeSpan` helper in `SharedResourceWarning.js` constructs an HTML string using string concatenation without proper HTML encoding. This unescaped string is then rendered via React's `dangerouslySetInnerHTML`. While current Kubernetes DNS-1123 name validation prevents immediate exploitation, any future relaxation of this validation or an alternative data source could enable stored Cross-Site Scripting (XSS) in the hub console. This could allow an attacker to inject malicious scripts into web pages viewed by other users.
Statement: This vulnerabili
VulDB
Microsoft Office up to LTSC for Mac 2024 buffer overflow (EUVD-2026-56749)
vuldb·2026-08-17·CVSS 7.8
CVE-2026-66807 [HIGH] Microsoft Office up to LTSC for Mac 2024 buffer overflow (EUVD-2026-56749)
A vulnerability was found in Microsoft Office up to LTSC for Mac 2024 and classified as problematic. This affects an unknown function. The manipulation results in buffer overflow.
This vulnerability is known as CVE-2026-66807. Attacking locally is a requirement. No exploit is available.
A patch should be applied to remediate this issue.
GHSA
Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
ghsa_unreviewed·2026-08-11
CVE-2026-66807 [HIGH] CWE-121 Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Stack-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
No detection rules found.
No public exploits indexed.
Rapid7
Patch Tuesday - August 2026
blogs_rapid7·2026-08-11·CVSS 7.2
CVE-2026-68821 [HIGH] Patch Tuesday - August 2026
Microsoft is publishing 421 vulnerabilities on August 2026 Patch Tuesday , including 236 vulnerabilities in Windows. This is lower volume than last month’s record-breaking behemoth, but still one of the largest Patch Tuesday totals ever. 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 one of the vulnerabilities published today, as well as public disclosure for two others, although the Notable CVEs section of the Security Update Guide omits one of these. As usual, browser vulns are not included in the Patch Tuesday count above, but unusually, Microsoft does not appear to have published any desktop browser security patches so far this month.
## Summary charts
## Summary tables
#
Qualys
Microsoft Patch Tuesday, August 2026 Security Update Review
blogs_qualys·2026-08-11
CVE-2026-72971 Microsoft Patch Tuesday, August 2026 Security Update Review
## Table of Contents
Microsoft Patch Tuesday forAugust2026
Zero-day Vulnerabilities Patched inAugustPatch Tuesday Edition
Critical Severity Vulnerabilities Patched inAugustPatch Tuesday Edition
Other Microsoft Vulnerability Highlights
Microsoft Release Summary
Qualys Monthly Webinar Series
The August 2026 Microsoft Patch Tuesday release delivers security fixes for vulnerabilities affecting a wide range of Microsoft products and services. As attackers continue to exploit unpatched vulnerabilities, timely patching remains critical for reducing exposure and strengthening enterprise security.
## Microsoft Patch Tuesday for August 2026
This month’s release addresses 421 vulnerabilities, including 62 critical and 357 important-severity vulnerabilities.
In this month’s updates, Microsof
Sans Isc
Microsoft Patch Tuesday August 2026, (Tue, Aug 11th)
blogs_sans_isc·2026-08-11·CVSS 7.8
CVE-2026-68820 [HIGH] Microsoft Patch Tuesday August 2026, (Tue, Aug 11th)
Microsoft Patch Tuesday August 2026
Published: 2026-08-11. Last Updated: 2026-08-11 17:54:49 UTC
by Renato Marinho (Version: 1)
0 comment(s)
This month we got patches for 418 vulnerabilities. Of these, 62 are critical, 1 is being exploited in the wild, and 2 were publicly disclosed as zero-days. Notable fixes include Windows privilege escalation, container tampering, and critical QUIC and DNS Server remote code execution bugs.
A few vulnerabilities worth mentioning:
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability (CVE-2026-68820)
This Important-severity elevation of privilege vulnerability is listed by Microsoft as exploited in the wild but not publicly disclosed, and it has a CVSS score of 7.0. The flaw is a use-after-free issue in the Windows Ancil
Talos
Microsoft Patch Tuesday for August 2026 — Snort rules and prominent vulnerabilities
blogs_talos·2026-08-11·CVSS 9.4
CVE-2026-68820 [CRITICAL] Microsoft Patch Tuesday for August 2026 — Snort rules and prominent vulnerabilities
## Microsoft Patch Tuesday for August 2026 — Snort rules and prominent vulnerabilities
Microsoft has released its monthly security update for August 2026, which includes 421 vulnerabilities affecting a range of products, including 62 that Microsoft marked as "critical."
Microsoft notes that 1 of the vulnerabilities disclosed this month have been exploited in the wild
CVE-2026-68820 is an elevation of privilege vulnerability affecting Windows Ancillary Function Driver for WinSock. A Use After Free vulnerability could allow an authorized attacker to elevate privileges locally. This vulnerability has a CVSS base score of 7.0.
Out of 62 "critical" vulnerabilities, 40 are remote code execution (RCE) vulnerabilities.
Microsoft considers exploitation of the following vulnerabilities more lik
Crowdstrike
August 2026 Patch Tuesday: One Exploited Zero-Day and 62 Critical Vulnerabilities Among 415 CVEs
blogs_crowdstrike
CVE-2026-68820 August 2026 Patch Tuesday: One Exploited Zero-Day and 62 Critical Vulnerabilities Among 415 CVEs
August 2026 Patch Tuesday: One Exploited Zero-Day and 62 Critical Vulnerabilities Among 415 CVEs Aug 11, 2026
CrowdStrike Threat Hunts for Shell Command Obfuscation on VMware ESX Aug 07, 2026
Expanding AI Benchmarks in Cybersecurity Beyond Vulnerability Discovery Aug 06, 2026
Secure Agent Harness Execution: Preventing Escape Aug 04, 2026
August 2026 Patch Tuesday: One Exploited Zero-Day and 62 Critical Vulnerabilities Among 415 CVEs Aug 11, 2026
CrowdStrike Threat Hunts for Shell Command Obfuscation on VMware ESX Aug 07, 2026
Expanding AI Benchmarks in Cybersecurity Beyond Vulnerability Discovery Aug 06, 2026
Secure Agent Harness Execution: Preventing Escape Aug 04, 2026
Video Highlights the 4 Key Steps to Successful Incident Response Dec 02, 2019
Helping Non-Security Stakeholders
Bugzilla
CVE-2026-66807 console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
bugzilla·2026-07-30·CVSS 7.8
CVE-2026-66807 [HIGH] CVE-2026-66807 console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
CVE-2026-66807 console: console: potential XSS via dangerouslySetInnerHTML with unescaped resource name in getCodeSpan
The getCodeSpan helper in SharedResourceWarning.js constructs an HTML string via string concatenation: `getCodeSpan = (text) => '' + text + ''` with no HTML encoding. The result is rendered via React's dangerouslySetInnerHTML with `deployingSubscription`, which is a Subscription metadata.name value.
Kubernetes DNS-1123 name validation ([a-z0-9.-]) currently prevents injection of HTML metacharacters (<>"'), so this is not exploitable today. However, the dangerous sink is one upstream data-source change away from XSS — any relaxation of the name validation or alternative data source feeding text into getCodeSpan would enable stored XSS in the hub console.
Affected file: f
2026-08-11
Published