CVE-2026-27748
Avira Internet Security Arbitrary File Deletion via Improper Link Resolution
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.8
Avira Internet Security Arbitrary File Deletion via Improper Link Resolution
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.
- Record
CVE-2026-27748- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-59
- Updated
- 2026-11-02
EUVDEUVD-2026-9820
7.8
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.
- Record
EUVD-2026-9820- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-w3vx-x8fj-r29m
8.5
Avira Internet Security contains an improper link resolution vulnerability in the Software...
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.
- Record
GHSA-w3vx-x8fj-r29m- CVSS 4.0
- 8.5 High
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-59
- Updated
- 2026-11-02
NVD
7.8
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.
- Record
CVE-2026-27748- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-59
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-27748 is a high vulnerability (CVSS 7.8) in Avira Internet Security, published March 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 9th percentile. No source names a fixed version.
References
support.avira.com/hc/en-us/articles/360010656158-Current-Avira-versions
avira.com/en/internet-security
gendigital.com/us/en/contact-us/security-advisories
nvd.nist.gov/vuln/detail/CVE-2026-27748
blog.quarkslab.com/avira-deserialize-delete-and-escalate-the-proper-way-to-use-an-av.html
vulncheck.com/advisories/avira-internet-security-arbitrary-file-deletion-via-improper-link-resolution
github.com/advisories/GHSA-w3vx-x8fj-r29m