CVE-2026-88099

Status: AnalyzedMedium (5.9)—

Severity5.9Medium · CVSS 3.1

Exploitation probability0.82 %higher than 56% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

Uncaught exception in Windows Failover Cluster allows an unauthorized attacker to deny service over a network.

CVSS

Base score: 5.9
Version: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.82 %
Percentile among all scored CVEs: 56
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access90 %
Primary impactT1499 Endpoint Denial of Serviceimpact70 %

Vector AV:N/PR:N/UI:N (red sin privilegios) y descripción de excepción no capturada que permite denegar el servicio al atacante no autorizado.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Affected technologies (3)

Microsoft — Windows Server 2019 Microsoft — Windows Server 2022 Microsoft — Windows Server 2025

CWEs

CWE-248

References

Show 1 references

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88099

Raw JSON (NVD)

Show

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