CVE-2026-82964
Awaiting Analysis Awaiting Analysis - Queue

BaseFortify

Vulnerability report for CVE-2026-82964, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-09-16

Last updated on: 2026-09-17

Assigner: NortonLifeLock Inc.

Description

Improper preservation of permissions in the Avast sandbox minifilter driver (aswSnx.sys) on Windows allows a local, low-privileged attacker executing inside the sandbox to escape file isolation and escalate to SYSTEM. When the sandbox virtualizes a file it copies the original security descriptor, but the driver opened the virtualization target object with GENERIC_WRITE and FILE_WRITE_ATTRIBUTES only, omitting WRITE_DAC. Every attempt to apply the original DACL therefore failed, and the failure was discarded silently, leaving virtualized copies of sensitive files with permissive permissions. Because the IRP_MJ_CREATE callback additionally did not strip WRITE_DAC for sensitive directories, a sandboxed process could rewrite the security descriptor of a virtualized object, read the virtualized copy of the SAM database, extract local NTLM password hashes and execute code as SYSTEM. The absence of an IRP_MJ_SET_SECURITY callback in the driver's operation registration table is a related defense-in-depth gap, but it is not the control that prevents this attack.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-09-16
Last Modified
2026-09-17
Generated
2026-09-20
EPSS Evaluated
N/A
NVD

Affected Vendors & Products

Currently, no data is known.

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-281 The product does not preserve permissions or incorrectly preserves permissions when copying, restoring, or sharing objects, which can cause them to have less restrictive permissions than intended.
CWE-653 The product does not properly compartmentalize or isolate functionality, processes, or resources that require different privilege levels, rights, or permissions.
CWE-862 The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
AI Quick Actions have not been generated yet.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-82964. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart