CVE-2026-66808
published 2026-08-11CVE-2026-66808: Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
PriorityP262high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
2.04%
81.0th percentile
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_sharepoint_enterprise_server_2016 | >= 16.0.0 < 16.0.5565.1001 | 16.0.5565.1001 |
| microsoft | microsoft_sharepoint_server_2019 | >= 16.0.0 < 16.0.10417.20198 | 16.0.10417.20198 |
| microsoft | microsoft_sharepoint_server_subscription_edition | >= 16.0.0 < 16.0.19725.20522 | 16.0.19725.20522 |
| microsoft | sharepoint_server | < 16.0.19725.20522 | 16.0.19725.20522 |
| microsoft | sharepoint_server | — | — |
| microsoft | sharepoint_server | — | — |
| multicluster-engine | hypershift-addon-rhel9-operator | — | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_redhat8.7HIGH
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VulDB
hypershift-addon-operator argument injection (EUVD-2026-56750)
vuldb·2026-08-17·CVSS 8.8
CVE-2026-66808 [HIGH] hypershift-addon-operator argument injection (EUVD-2026-56750)
A vulnerability was found in hypershift-addon-operator and classified as very critical. Affected by this vulnerability is an unknown functionality. Executing a manipulation can lead to argument injection.
This vulnerability is tracked as CVE-2026-66808. The attack can be launched remotely. No exploit exists.
GHSA
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
ghsa_unreviewed·2026-08-11
CVE-2026-66808 [HIGH] CWE-502 Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
Red Hat
hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
vendor_redhat·2026-08-06·CVSS 8.7
CVE-2026-66808 [HIGH] CWE-88 hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
A flaw was found in hypershift-addon-operator. A hub-cluster administrator with write access to the hypershift-operator-install-flags ConfigMap can inject malicious command-line arguments into the privileged install Job. This vulnerability, known as argument injection, allows the attacker to pull arbitrary container images and gain full administrative control (cluster-admin code execution) on managed spoke clusters.
Statement: This Important flaw in Multicluster Engine for Kubernetes allows a hub-cluster namespace administrator with write access to the `hypershift-operator-install-flags` ConfigMap to inject arbitrary command-line argu
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.
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Tenable
Microsoft's August 2026 Patch Tuesday Addresses 398 CVEs (CVE-2026-68820)
blogs_tenable·2026-08-11·CVSS 7.0
CVE-2026-68820 [HIGH] Microsoft's August 2026 Patch Tuesday Addresses 398 CVEs (CVE-2026-68820)
## Microsoft's August 2026 Patch Tuesday Addresses 398 CVEs (CVE-2026-68820)
42 Critical
355 Important
1 Moderate
0 Low
Microsoft addresses 398 CVEs in the eighth Patch Tuesday of 2026, with three zero-days, including one that was exploited in the wild.
Microsoft patched 398 CVEs in its August 2026 Patch Tuesday release, with 42 rated critical, 355 rated as important and one rated as moderate. Our counts omitted two CVEs assigned by MITRE; CVE-2026-6726 and CVE-2026-6727.
This month’s update includes patches for:
.NET
.NET Core
.NET Framework
AMD Zen
Active Directory Certificate Services (AD CS)
Application Information Services
Azure Active Directory
Azure CycleCloud
Azure Monitor Agent
Azure Storage Explorer
Capability Access Management Service (camsvc)
Desktop Window M
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
Bugzilla
CVE-2026-66808 hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
bugzilla·2026-07-31
CVE-2026-66808 [HIGH] CVE-2026-66808 hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
CVE-2026-66808 hypershift-addon-operator: hypershift-addon-operator: unsanitized hub ConfigMap data passed as CLI arguments to privileged install Job (argument injection)
A flaw was found in hypershift-addon-operator. The buildOtherInstallFlags() function in pkg/install/hypershift.go reads arbitrary key-value pairs from the hypershift-operator-install-flags ConfigMap and appends them unsanitized as CLI arguments to the hypershift install Job. A hub-cluster namespace administrator with write access to this ConfigMap can inject arbitrary flags into the privileged install Job, enabling arbitrary image pull and cluster-admin code execution on managed spoke clusters.
The vulnerable code path is: pkg/install/hypershift.go lines 428-506 (buildOtherInstallFlags) and pkg/install/install_job.go li
2026-08-11
Published