Source: Microsoft · Limited verification•Last verified: •Collection Degraded
CVE-2026-89969Unknown / EvaluatingCritical (raw)CVSS 9.8
nvmet-tcp: fix out-of-bounds write when receiving an over-long PDU
Published: 17 Sept 2026•Last updated: 02 Oct 2026, 07:53 AM IST•Source identifier: Unknown
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
9.8Critical (raw)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U
Metric sourceMicrosoft MSRC CVRF
EPSS probability
0.7%0.007
Percentile53rd
Weakness type
—
No further CWE recorded
Remediation
Patch status unknown
No fixed version or KB recorded
Why It Matters
Analysis dossierWhy It Matters
— Pending vendor disclosure
SOC priority
High Severity / Review
Actively exploited
Unknown
Publicly disclosed
Unknown
Risk basis: Critical CVSS without confirmed KEV exploitation
Affected Products & Remediation
2 source-backed productsAffected products and versions (source)
Recorded patch / KBNot provided by source
Vendor or catalog guidance (source)
- Microsoft MSRC: Release Notes
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)
- Unknown
- 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 network-unauthenticated (CVSS AV:N, CVSS PR:N, CVSS UI:N)
Exposure
- 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 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 update is installed and the CVE is no longer reported.Telemetry: DeviceTvmSoftwareVulnerabilities · A follow-up inventory check verifies remediation. · Rule network-unauthenticated
CISA KEV Record
CISA KEV status was not determined for this record.
Change History & Source Data
— No recorded material change
- CNA / source
- Unknown
- Record status · verification
- UPDATED · Unknown
- CPE
- Unknown
Evidence & Provenance
Linked by the query's stored exact CVE association. Review required tables and validation status before use.
Detection Hunting Query
Target: DeviceTvmSoftwareVulnerabilities•Defender XDR
Detect endpoints exposed to CVE-2026-89969
Purpose: Exposure assessment (Category: Exposure Check)Why linked: Query metadata names CVE-2026-89969
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2026-89969"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel descSchema Checked · Not runtime validatedSource: SecOps Signal deterministic template · Limited verificationStatic screening: Passed structure and schema checks; tenant execution is not verified.
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.