Avira Internet Security contains a time-of-check time-of-use (TOCTOU) vulnerability in the Optimizer component. A privileged service running as SYSTEM identifies directories for cleanup during a scan phase and subsequently deletes them during a separate cleanup phase without revalidating the target path. A local attacker can replace a previously scanned directory with a junction or reparse point before deletion occurs, causing the privileged process to delete an unintended system location. This may result in deletion of protected files or directories and can lead to local privilege escalation, denial of service, or system integrity compromise depending on the affected target.
History

Fri, 06 Mar 2026 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 06 Mar 2026 15:30:00 +0000

Type Values Removed Values Added
First Time appeared Gen Digital
Gen Digital avira Internet Security
Vendors & Products Gen Digital
Gen Digital avira Internet Security

Fri, 06 Mar 2026 11:15:00 +0000

Type Values Removed Values Added
First Time appeared Avira
Avira avira Internet Security Suite
CPEs cpe:2.3:a:avira:avira_internet_security_suite:*:*:*:*:*:windows:*:*
Vendors & Products Avira
Avira avira Internet Security Suite

Thu, 05 Mar 2026 22:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Thu, 05 Mar 2026 14:30:00 +0000

Type Values Removed Values Added
Description Avira Internet Security contains a time-of-check time-of-use (TOCTOU) vulnerability in the Optimizer component. A privileged service running as SYSTEM identifies directories for cleanup during a scan phase and subsequently deletes them during a separate cleanup phase without revalidating the target path. A local attacker can replace a previously scanned directory with a junction or reparse point before deletion occurs, causing the privileged process to delete an unintended system location. This may result in deletion of protected files or directories and can lead to local privilege escalation, denial of service, or system integrity compromise depending on the affected target.
Title Avira Internet Security Optimizer TOCTOU
Weaknesses CWE-367
References
Metrics cvssV4_0

{'score': 8.5, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-03-06T18:17:44.243Z

Reserved: 2026-02-23T21:38:48.842Z

Link: CVE-2026-27750

cve-icon Vulnrichment

Updated: 2026-03-06T18:17:38.584Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-03-05T15:16:12.153

Modified: 2026-03-05T23:16:20.703

Link: CVE-2026-27750

cve-icon Redhat

No data.