CVE-2026-27748

Avira Internet Security contains an improper link resolution vulnerability in the Software Updater component. During the update process, a privileged service running as SYSTEM deletes a file under C:\\ProgramData without validating whether the path resolves through a symbolic link or reparse point. A local attacker can create a malicious link to redirect the delete operation to an arbitrary file, resulting in deletion of attacker-chosen files with SYSTEM privileges. This may lead to local privilege escalation, denial of service, or system integrity compromise depending on the targeted file and operating system configuration.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html	Third Party Advisory
https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions	Release Notes
https://www.avira.com/en/internet-security	Product
https://www.vulncheck.com/advisories/avira-internet-security-arbitrary-file-deletion-via-improper-link-resolution	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:avira:internet_security:*:*:*:*:*:windows:*:*

History

No history.

Information

Published : 2026-03-05 15:16

Updated : 2026-03-13 01:22

NVD link : CVE-2026-27748

Mitre link : CVE-2026-27748

CVE.ORG link : CVE-2026-27748

JSON object : View

Products Affected

avira

internet_security

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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Un atacante local puede crear un enlace malicioso para redirigir la operaci\u00f3n de eliminaci\u00f3n a un archivo arbitrario, resultando en la eliminaci\u00f3n de archivos elegidos por el atacante con privilegios de SYSTEM. Esto puede llevar a una escalada de privilegios local, denegaci\u00f3n de servicio o compromiso de la integridad del sistema dependiendo del archivo objetivo y la configuraci\u00f3n del sistema operativo."}], "lastModified": "2026-03-13T01:22:40.027", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:avira:internet_security:*:*:*:*:*:windows:*:*", "vulnerable": true, "matchCriteriaId": "DFB6EFB7-8777-4A9B-9A00-2FBEE12A7090", "versionEndExcluding": "1.1.114.3113"}], "operator": "OR"}]}], "sourceIdentifier": "disclosure@vulncheck.com"}