CVE-2026-69348

Status: AnalyzedHigh (7.8)—

Heap-based buffer overflow in Windows Win32K allows an authorized attacker to elevate privileges locally.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.33%
Percentile among all scored CVEs: 24
Score date: 10/5/2026

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.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Primary impactT1059 Command and Scripting Interpreterexecution90 %

Buffer overflow local (AV:L, PR:L) en Win32K sin UI permite escalada de privilegios. Acceso local ya requerido (PR:L) hace que T1068 sea la vía de explotación. Ejecución de comandos (T1059) es el impacto natural post-escalada.

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Affected technologies (4)

Microsoft — Windows 11 24h2 Microsoft — Windows 11 25h2 Microsoft — Windows 11 26h1 Microsoft — Windows Server 2025

CWEs

CWE-122

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69348

Raw JSON (NVD)

Show

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