CVE-2026-27748

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. 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.

7.8 /10

CVSS v3 : HIGH

V3 Legend

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

13 Mar 2026, 01:22

Type Values Removed Values Added
CPE cpe:2.3:a:avira:internet_security:*:*:*:*:*:windows:*:*
First Time Avira internet Security
Avira
References () https://blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html - () https://blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html - Third Party Advisory
References () https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions - () https://support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions - Release Notes
References () https://www.avira.com/en/internet-security - () https://www.avira.com/en/internet-security - Product
References () https://www.vulncheck.com/advisories/avira-internet-security-arbitrary-file-deletion-via-improper-link-resolution - () https://www.vulncheck.com/advisories/avira-internet-security-arbitrary-file-deletion-via-improper-link-resolution - Third Party Advisory
Summary
  • (es) Avira Internet Security contiene una vulnerabilidad de resolución de enlaces incorrecta en el componente Software Updater. Durante el proceso de actualización, un servicio privilegiado ejecutándose como SYSTEM elimina un archivo bajo C:\\ProgramData sin validar si la ruta se resuelve a través de un enlace simbólico o un punto de reanálisis. Un atacante local puede crear un enlace malicioso para redirigir la operación de eliminación a un archivo arbitrario, resultando en la eliminación de archivos elegidos por el atacante con privilegios de SYSTEM. Esto puede llevar a una escalada de privilegios local, denegación de servicio o compromiso de la integridad del sistema dependiendo del archivo objetivo y la configuración del sistema operativo.

05 Mar 2026, 23:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.8

05 Mar 2026, 15:16

Type Values Removed Values Added
New CVE
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')