CVE-2022-3368

Executive Summary

CVE-2022-3368 is a privilege escalation vulnerability in the Software Updater component of Avira Security for Windows. An attacker with low-level write access to the filesystem can exploit this flaw to escalate privileges to a higher privilege level in specific scenarios. The vulnerability was disclosed and remediated in Avira Security version 1.1.72.30556, but no public exploit code or technical write-up has been released. With a CVSS score of 7.3, the flaw poses a significant risk to enterprise environments running unpatched versions of Avira Security.

Technical Analysis

The vulnerability exists within the Software Updater functionality of Avira Security for Windows. Based on the NVD description, the core issue is that the Software Updater component does not adequately enforce privilege boundaries when interacting with the filesystem. An attacker who has write access to the filesystem — even at a low-privilege level — can exploit the Software Updater's operations to escalate their privileges in "certain scenarios."

The attack surface is the Software Updater component itself, which runs as part of Avira Security for Windows. This component is responsible for managing and updating third-party software installed on the Windows host. Because this functionality typically requires elevated privileges to modify system files and software installations, the Software Updater likely runs with higher privileges than a standard user process.

The vulnerability class is consistent with an insecure file handling or path traversal weakness, where the Software Updater may follow attacker-controlled file paths or write to locations that can be influenced by a local attacker. The NVD description does not disclose the precise technical mechanism (e.g., DLL hijacking, symlink attack, or insecure file permissions), and insufficient technical detail is available from the CNA to make a definitive determination of the exact flaw type.

The fact that write access to the filesystem is a precondition for exploitation suggests the vulnerability involves a local race condition, a TOCTOU (Time-of-Check-to-Time-of-Use) issue, or improper handling of a writable directory where the Software Updater performs its operations. The attacker would need to be on the local system and have the ability to create or modify files in a path that the Software Updater later accesses with elevated privileges.

Per the patch information, the issue was resolved in Avira Security version 1.1.72.30556. Patch confidence is rated 2/4 (CLAIMED), meaning the patch is only reported by a single source (the CNA) and has not been independently confirmed by a second party or vendor advisory.

Exploitation Scenarios

The following attack chain is inferred from the vulnerability class and NVD description. No public PoC is available; the attack chain is inferred from the vulnerability description.

1) Reconnaissance / Target Identification: The attacker must first gain a foothold on the target Windows system as an unprivileged user (or have any level of local access that allows filesystem write operations). This could be achieved through phishing, credential theft, or by exploiting another vulnerability. The attacker then identifies that Avira Security for Windows is installed and that the version is earlier than 1.1.72.30556, confirming the vulnerable state.

2) Triggering the Flaw: Once on the system, the attacker leverages their existing filesystem write access to prepare a malicious file or directory structure in a location that the Software Updater will process. The attack mechanism is at the file system interaction level — the attacker creates a file, directory, symlink, or modifies file permissions in a path that the Software Updater accesses during its update operations. The exact technique is not disclosed, but the attacker is likely to use a symbolic link, NTFS junction point, or directory traversal to redirect the Software Updater's write operations to a privileged location (e.g., Program Files, System32, or a scheduled task directory).

3) Payload / Execution Method: When the Software Updater next runs (either on a schedule, user-triggered, or after a system event), it processes the attacker-controlled filesystem object. Due to the privilege escalation flaw, the Software Updater performs a file operation (create, write, or overwrite) with elevated privileges to a location chosen by the attacker. The attacker's payload — e.g., a malicious executable, DLL, or script — is placed in a privileged location and executed at the elevated privilege level.

4) Post-Exploitation Impact: After successful exploitation, the attacker achieves privilege escalation — potentially to SYSTEM or an administrative account — depending on the privilege level under which the Software Updater runs. The attacker can then disable security controls, install persistence mechanisms, exfiltrate sensitive data, move laterally within the network, or perform any other administrative action on the compromised host.

Limitations of the Attack: The attack requires local filesystem write access, meaning a remote attacker cannot exploit this vulnerability directly. The attack is limited to scenarios where the Software Updater actually processes the attacker-created filesystem objects, which may require the attacker to wait for a scheduled update or trigger the updater through some user or system action.

Impact Assessment

• CVSS Score: 7.3 (High). The vector indicates local attack vector (AV:L), low attack complexity (AC:L), low privileges required (PR:L), and user interaction required (UI:R). The integrity and confidentiality impacts are both high, with availability also high.

• Business Impact: Successful exploitation results in full compromise of the affected endpoint. The attacker gains privileges necessary to disable Avira Security itself, undermining endpoint protection and potentially leaving the broader enterprise network exposed to further attack. Confidentiality impact is high — the attacker can read any data on the host. Integrity impact is high — the attacker can modify system files, install backdoors, or tamper with security logs. Availability impact is high — the attacker can render the system unbootable or cause a denial of service.

• Affected Systems: All Windows systems running Avira Security versions prior to 1.1.72.30556 with the Software Updater component enabled. This includes enterprise environments where Avira Security is centrally managed, as well as individual consumer machines.

• Blast Radius: The blast radius is limited to the local host because the attack requires local filesystem write access. However, on enterprise networks where avira-managed endpoints are common, an attacker who compromises one endpoint and escalates privileges could use that position as a launch point for lateral movement to other systems, potentially expanding the overall impact across the organization.

• EPSS Context: The EPSS score of 0.00838 (54.5th percentile) indicates a relatively low probability of active exploitation in the wild. However, this should not be interpreted as low risk — the score reflects low exploitation frequency, not low impact.

Detection Guidance

Sigma Rule

title: Avira Software Updater Privilege Escalation Attempt
id: 5f3a9c1d-8f47-4a2e-9b41-7e2c3d8f1a0b
status: experimental
description: Detects suspicious file operations associated with Avira Software Updater that may indicate privilege escalation attempts (CVE-2022-3368)
author: Valtersit Threat Intelligence
date: 2024/01/15
tags:
    - attack.privilege_escalation
    - attack.t1068
    - cve.2022-3368
logsource:
    category: file_event
    product: windows
detection:
    selection_avira_process:
        Image|endswith:
            - '\avira\software_updater.exe'
            - '\avira\sched.exe'
            - '\avira\avira_software_updater.exe'
    selection_sensitive_paths:
        TargetFilename|startswith:
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
            - 'C:\Program Files\'
            - 'C:\Program Files (x86)\'
    selection_suspicious_extensions:
        TargetFilename|endswith:
            - '.exe'
            - '.dll'
            - '.sys'
            - '.bat'
            - '.ps1'
    condition: selection_avira_process and selection_sensitive_paths and selection_suspicious_extensions
    timeframe: 5m
level: high
falsepositives:
    - Legitimate software update operations performed by Avira
    - Avira updater writing to its own installation directory

YARA Rule

rule AVIRA_SOFTWARE_UPDATER_PRIVESC_CVE_2022_3368 {
    meta:
        author = "Valtersit Threat Intelligence"
        description = "Detects files associated with Avira Software Updater privilege escalation attempts (CVE-2022-3368)"
        date = "2024-01-15"
        cve = "CVE-2022-3368"
        severity = "high"
    strings:
        $s1 = "software_updater" ascii wide nocase
        $s2 = "avira_update" ascii wide nocase
        $s3 = "C:\\Program Files\\Avira" ascii wide nocase
        $s4 = "sched_clt" ascii wide nocase
        $s5 = "updater" ascii wide nocase
        $s6 = "regsvr32" ascii wide nocase
        $s7 = "schtasks" ascii wide nocase
    condition:
        (uint16(0) == 0x5A4D) and
        (2 of ($s1, $s2, $s3, $s4) or
        (all of ($s5, $s6, $s7)))
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2022-3368 Avira Software Updater Privesc Attempt"; content:"avira"; nocase; content:"update"; nocase; content:"software"; nocase; pcre:"/(?:\.exe|\.dll|\.sys|\.ps1|\.bat)$/Ui"; classtype:attempted-admin; sid:20223368; rev:1; metadata:created_at 2024_01_15, updated_at 2024_01_15, cve CVE-2022-3368, mitre_tactic_id TA0004, mitre_technique_id T1068;)

Elastic Detection

// EQL query to detect Avira Software Updater writing to sensitive paths
sequence with maxspan=5m
  [process where process.name : "*.exe" and process.executable : "*\\Avira\\*"
    and process.name : ("software_updater*", "sched*", "avira*")]
  [file where event.action : ("write", "create", "modify") and
    file.path : ("C:\\Windows\\System32\\*", "C:\\Windows\\SysWOW64\\*",
                 "C:\\Program Files\\*", "C:\\Program Files (x86)\\*")
    and file.extension : ("exe", "dll", "sys", "bat", "ps1")]

Splunk SPL Query

index=windows sourcetype=XmlWinEventLog:Security OR sourcetype=WinEventLog:Application
| search (EventCode=4688 OR EventCode=1) AND (Process_Name="*Avira*")
| search CommandLine="*software_updater*" OR CommandLine="*sched*" OR CommandLine="*update*"
| rex field=CommandLine "(?<file_path>[A-Za-z]:\\\\[^\s]+\.(exe|dll|sys|bat|ps1))"
| where file_path LIKE "C:\\Windows\\System32\\%" OR file_path LIKE "C:\\Program Files\\%"
| table _time, host, User, Process_Name, CommandLine, file_path
| sort - _time

Wazuh OSSEC Rule

<group name="avira_security,">
    <rule id="104500" level="12">
        <decoded_as>syslog</decoded_as>
        <field name="program_name">avira</field>
        <description>Avira Software Updater writing to sensitive system directories - possible CVE-2022-3368 exploitation</description>
        <match>software_updater</match>
        <regex>write|create|modify|rename</regex>
        <regex>C:\\Windows\\System32|C:\\Program Files</regex>
        <group>privilege_escalation,attack.t1068,</group>
        <mitre><id>T1068</id><name>Exploitation for Privilege Escalation</name></mitre>
        <info>Avira Security Software Updater has performed a file operation on a sensitive system path. This may indicate an attempt to exploit CVE-2022-3368.</info>
        <options>no_full_log</options>
    </rule>

    <rule id="104501" level="10">
        <if_sid>104500</if_sid>
        <field name="file_extension">\.(exe|dll|sys|bat|ps1)$</field>
        <description>Avira Software Updater writing an executable file to a sensitive path - high confidence CVE-2022-3368 exploitation</description>
        <group>privilege_escalation,attack.t1068,</group>
        <mitre><id>T1068</id><name>Exploitation for Privilege Escalation</name></mitre>
    </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 2/4 (CLAIMED — single source claims patch, not independently confirmed)

1) Immediate Mitigations:

• Upgrade Avira Security to version 1.1.72.30556 or later as soon as possible, as this is the only confirmed remediation.
• If immediate upgrade is not possible, restrict the Software Updater's filesystem access by applying Windows integrity-level constraints or run Avira Security in a sandboxed environment where feasible.
• Implement and enforce least-privilege principles on all endpoints: ensure standard users cannot write to system paths (e.g., C:\Windows, C:\Program Files) regardless of the vulnerability.
• Monitor endpoints running Avira Security for anomalous file operations from the Avira processes, and alert on writes to sensitive directories.
• Audit and restrict local user accounts to reduce the attack surface — the vulnerability requires local filesystem write access, so minimizing low-privileged user accounts reduces exposure.

2) Patch/Upgrade Steps:

• Visit the official Avira (NortonLifeLock) website and download the latest version of Avira Security for Windows.
• Verify the current installed version by opening Avira Security → Help → About, or by checking the installed program version in Windows Settings.
• Install the update to version 1.1.72.30556 or higher. For enterprise deployments, use the Avira management console to push the update to all managed endpoints.
• After patching, verify the Software Updater function still operates correctly and that the version is confirmed as updated on all systems.
• While patch confidence is 2/4 and independently unconfirmed, treat the fix as authoritative since it originates from the CNA. Continue to monitor for additional vendor confirmations or a supplementary advisory.

3) Long-Term Hardening:

• Enable and enforce Windows Defender Exploit Guard (or equivalent) on endpoints running security software to mitigate privilege escalation techniques.
• Implement a formal patch management program with regular vulnerability scanning to ensure all software, including security products, is up to date.
• Use application allowlisting (e.g., Windows Defender Application Control or AppLocker) to block unauthorized executables and scripts from running, even if placed on disk by privilege escalation.
• Deploy Endpoint Detection and Response (EDR) tools that can detect file-system based privilege escalation attempts in real time.
• Ensure proper logging is enabled (process creation, file audit, PowerShell script block logging) across Windows endpoints for forensic visibility.
• Implement active threat hunting procedures to search for indicators of privilege escalation across the enterprise environment.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2022-3368 — CVE-2022-3368, CVSS score 7.3, official NVD description.
2. CNA Coordination: NortonLifeLock (CNA) advisory — disclosed the vulnerability in Avira Security for Windows and confirmed the fix in version 1.1.72.30556.
3. CVEDetails: https://www.cvedetails.com/cve/CVE-2022-3368 — Additional CVE metadata and vendor information.
4. ATT&CK Framework: https://attack.mitre.org/techniques/T1068/ — MITRE ATT&CK technique for Exploitation for Privilege Escalation.
5. CISA KEV: CVE-2022-3368 is NOT listed on the CISA Known Exploited Vulnerabilities catalog as of the latest update. No known threat actor campaigns or exploit-in-the-wild evidence have been reported for this vulnerability.

Note: No public proof-of-concept, exploit code, or Nuclei template has been released for CVE-2022-3368 at the time of this report. Exploitation activity in the wild has not been observed.