CVE WatchSep 16, 2026

CVE-2026-82964

Improper preservation of permissions in the Avast sandbox minifilter driver (aswSnx.sys) on Windows allows a local, low-privileged attacker

CVSS

8.8

High

EPSS

—

KEV

—

Exploit Today

—

0-100

Published: Sep 16, 2026 · Last modified: Sep 16, 2026 · CWE-281 · CWE-653 · CWE-862

EPSS · 30d

Not enough EPSS history yet.

Technical 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.

Official references

Related CVEs

CVECVSSEPSSKEVRExploitTitleMod.

CVE-2026-18120—

—

———Concrete CMS before 9.5.3 exposed a legacy Express entry search endpoint that returned entry result JSON without invoking the canViewExpressEntries() permission check applied by the normal dashboard and CSV Export flow. An unauthenticated visitor who knew or discovered an Express entity identifier could enumerate that entity's entry search results, disclosing attribute values intended to be restricted to privileged users. For Express entities that do not support entry-specific permissions (i.e., supportsEntrySpecificPermissions() returns false), per-entry permission filtering is additionally disabled via EntryList::ignorePermissions(). The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Daniel Powell for reporting.2h CVE-2026-926016.5 MED

—

———Guns through 8.3.5 contains an improper access control vulnerability in SysNoticeController where requiredPermission defaults to false and is not overridden by any action methods. Authenticated users without assigned roles can exploit this to create, edit, delete, publish and retract system-wide notices affecting arbitrary users and departments.2h CVE-2026-926006.5 MED

—

———Guns through 8.3.5 contains an information disclosure vulnerability in SysUserController where /sysUser/detail and /sysUser/page endpoints omit requiredPermission configuration, causing the permission interceptor to skip RBAC validation for authenticated users. Attackers with any valid login token can retrieve sensitive user information including account names, real names, email addresses, phone numbers, last login IPs, and role assignments for all users in the system.3h CVE-2026-924026.3 MED

—

———A security flaw has been discovered in ChangeWeDer crm up to c07bd4c97141521af6475034bc58523beed51bbd. This issue affects the function index of the file UserController.java of the component top.upstudy.crm.controller.UserController. The manipulation results in missing authorization. The attack can be launched remotely. This product does not use versioning. This is why information about affected and unaffected releases are unavailable. The project was informed of the problem early through an issue report but has not responded yet.2h CVE-2026-87031—

—

———n Concrete CMS 9.2.0 through 9.5.3, the REST API user creation endpoint (POST /ccm/api/1.0/users, the add() method of concrete/src/Api/Controller/Users.php) did not perform a permission check before creating an account. As a result, any valid OAuth token carrying the users:add scope, including a client_credentials token with no associated user context, could create active, validated user accounts, bypassing email verification and administrator approval. Under default registration settings the created accounts could then edit page content, providing a path to stored cross-site scripting and further compromise. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.3h CVE-2026-87028—

—

———Concrete CMS 9 through 9.5.3 did not confirm that a board InstanceItem submitted to the custom-slot preview endpoint belonged to the board instance the requesting user was authorized to edit, and did not enforce page-view permission before generating page-backed summary content. As a result, an authenticated user holding edit-board-contents permission on a single board instance could submit the identifier of an item belonging to a different board instance and receive summary fields, including the page title and description, of an underlying page the same user was otherwise forbidden to view. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.3 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Pakung for reporting.3h