Answer in brief
CVE-2026-82964 records a High severity (CVSS 8.8) vulnerability in Avast sandbox privilege escalation via unpreserved DACLs on virtualized files in aswSnx.sys. The current sources do not mark it as known exploited. The current feed maps Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Security (generic), Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Security (generic), Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimate (generic), Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimate (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Security (generic), Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Security (generic), Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimate (generic), Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimate (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Securitygeneric | >=0 <26.8 | 26.8 |
| Gen Digital/Avast Free Antivirus, Avast One, Avast Premium Security, Avast Ultimate, Avast Business Securitygeneric | * | Not reported |
| Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimategeneric | >=0 <26.8 | 26.8 |
| Gen Digital/AVG Antivirus Free, AVG Internet Security, AVG Ultimategeneric | * | Not reported |
| Gen Digital/Norton Antivirus Plus, Norton 360 Standard, Norton 360 Deluxe, Norton 360 Advancedgeneric | >=0 <26.8 | 26.8 |
| Gen Digital/Norton Antivirus Plus, Norton 360 Standard, Norton 360 Deluxe, Norton 360 Advancedgeneric | * | Not reported |
Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 16, 2026
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.
Quoted source text, attributed separately from HOL analysis.