Source: Microsoft · Limited verification•Last verified: •Collection Degraded
CVE-2026-96248Unknown / EvaluatingImportant (raw)CVSS 7.5CWE-121
Windows Host Guardian Service Denial of Service Vulnerability
Published: 13 Oct 2026•Last updated: 13 Oct 2026, 12:30 PM IST•Source identifier: secure@microsoft.com
Dossier completeness: source-provided sections 3 / 3 · rule guidance available. Missing source facts count as incomplete.
CISA KEV catalog
Unknown
KEV status was not determined.
CVSS score
7.5Important (raw)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
Metric sourceMicrosoft MSRC CVRF
EPSS probability
1.1%0.011
Percentile66th
Weakness type
CWE-121
No further CWE recorded
Remediation
Patch status unknown
KB5126868, KB5126651, KB5126655, KB5126646
Why It Matters
Analysis dossierWhy It Matters
Stack-based buffer overflow in Windows Host Guardian Service allows an unauthorized attacker to deny service over a network.
SOC priority
High
Actively exploited
No
Publicly disclosed
Unknown
Risk basis: Microsoft or Microsoft-managed product relevance; HIGH severity; No confirmed exploitation signal in current enrichment
Affected Products & Remediation
12 source-backed productsAffected products and versions (source)
- Windows 10 Version 1607 for 32-bit Systems · version range not provided by source · Microsoft MSRC · Source
- Windows 10 Version 1607 for x64-based Systems · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2016 · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2016 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
- Windows 10 Version 1809 for 32-bit Systems · version range not provided by source · Microsoft MSRC · Source
- Windows 10 Version 1809 for x64-based Systems · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2019 · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2019 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2022 · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2022 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2025 · version range not provided by source · Microsoft MSRC · Source
- Windows Server 2025 (Server Core installation) · version range not provided by source · Microsoft MSRC · Source
Recorded patch / KBKB5126868, KB5126651, KB5126655, KB5126646
Vendor or catalog guidance (source)
- Microsoft MSRC: Install the security update KB5126868 listed by MSRC
- Microsoft MSRC: Install the security update KB5126651 listed by MSRC
- Microsoft MSRC: Install the security update KB5126655 listed by MSRC
- Microsoft MSRC: Install the security update KB5126646 listed by MSRC
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Unknown
- Exploited (source statement)
- No
- Publicly disclosed (source)
- Unknown
Suggested hunting (rule-based inference)
SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.
Matched microsoft-enterprise (Affected product: Windows 10 Version 1607 for 32-bit Systems, Vendor: Microsoft); network-unauthenticated (CVSS AV:N, CVSS PR:N, CVSS UI:N)
Exposure
- Identify affected Microsoft products and compare local builds with the MSRC advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · The MSRC product/build mapping establishes applicability. · Rule microsoft-enterprise
- Identify devices reporting this CVE and note which expose the affected service to untrusted networks.Telemetry: DeviceTvmSoftwareVulnerabilities · A network-reachable, no-privilege vector makes internet-facing instances the first exposure question. · Rule network-unauthenticated
Exploitation evidence
- Review the advisory's documented behavior on matching hosts before selecting a hunt.Telemetry: DeviceProcessEvents · Product family alone does not justify a CVE-specific detection. · Rule microsoft-enterprise
Show more (2)
Exploitation evidence
- Review inbound connections to the affected service from unexpected sources since the advisory date.Telemetry: DeviceNetworkEvents · Hunting hypothesis from the CVSS vector; it does not show that exploitation occurred. · Rule network-unauthenticated
Response
- Confirm the source-stated KB or mitigation on matching assets.Telemetry: DeviceTvmSoftwareVulnerabilities · A post-update inventory check verifies remediation. · Rule microsoft-enterprise
CISA KEV Record
CISA KEV status was not determined for this record.
Change History & Source Data
— No recorded material change
- CNA / source
- secure@microsoft.com
- Record status · verification
- UPDATED · Unknown
- CPE
- cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*, cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*, cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*, cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*, cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*, cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*
Evidence & Provenance
Detection Hunting Query
— No published hunting query names this record. Browse community and library queries instead.
Correlated briefings
SecOps Signal surfaces public advisory facts only. A missing value means the source has not published it, not that your environment is unaffected. No tenant inventory is connected.