ForticlientApplication · Fortinet
CVE-2021-44167
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedAn incorrect permission assignment for critical resource vulnerability [CWE-732] in FortiClient for Linux version 6.0.8 and below, 6.2.9 and below, 6.4.7 and below, 7.0.2 and below may allow an unauthenticated attacker to access sensitive information in log files and directories via symbolic links.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThis is a symlink-based permission bypass vulnerability in FortiClient for Linux. The software incorrectly assigns permissions to log files and directories, allowing an unauthenticated attacker to use symbolic links to access sensitive information that should be protected. This affects versions 6.0.8 and below, 6.2.9 and below, 6.4.7 and below, and 7.0.2 and below.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
ForticlientApplication
>= 6.0.0, <= 6.0.8>= 6.2.0, <= 6.2.9>= 6.4.0, <= 6.4.7>= 7.0.0, <= 7.0.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Verify FortiClient for Linux is installedRun 'dpkg -l | grep -i forticlient' or 'rpm -qa | grep -i forticlient' to list installed FortiClient packagesAffected if No FortiClient package is found - the system is not affected
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Identify installed FortiClient versionRun 'dpkg -l | grep forticlient' or check the application version via 'forticlient --version' if availableAffected if The installed version falls within 6.0.0-6.0.8, 6.2.0-6.2.9, 6.4.0-6.4.7, or 7.0.0-7.0.2 - the system may be affected
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Locate FortiClient log directoriesSearch for log directories typically under /var/log/ or the FortiClient installation directory, commonly /opt/forticlient/ or /usr/share/forticlient/Affected if Log directories exist and are world-readable or owned by root with weak permissions - the vulnerability may be present
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Inspect log directory permissions for world readabilityRun 'ls -la /var/log/ | grep -i forti' and check each log directory found for permissions like 755 or 777 instead of 750 or 700Affected if Directories or files within FortiClient log paths grant read access to all users (mode 755/777 or similar) - exploitation is possible
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Check for symlinks in or指向 FortiClient log directoriesRun 'ls -la /var/log/ | grep forti' and examine any entries starting with 'l' (symlinks), or use 'find /var/log -type l -path *forti* -exec ls -la {} \;'Affected if Unexpected symlinks exist within or pointing to FortiClient log directories - indicates potential exploitation attempt
A system is affected if FortiClient for Linux is installed with a version in the ranges 6.0.0-6.0.8, 6.2.0-6.2.9, 6.4.0-6.4.7, or 7.0.0-7.0.2 AND the log directories have overly permissive access controls that allow unauthenticated symlink-based access to sensitive files.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scopedUpgrade FortiClient for Linux to version 6.0.9, 6.2.10, 6.4.8, 7.0.3 or later as provided by Fortinet. If immediate patching is not possible, restrict access to log directories and monitor for unauthorized symlink creation.
FortiClient for Linux 7.0.3 or later (7.2.x recommended if available)
- 1. Identify the currently installed FortiClient for Linux version using 'forticlient --version' or checking the package manager.
- 2. Determine which upgrade path applies based on your current version (6.0.x, 6.2.x, 6.4.x, or 7.0.x).
- 3. Note that versions 6.0.x, 6.2.x, and 6.4.x are End of Life (EOL) - consider upgrading to the 7.0.x branch or later.
- 4. Download the latest FortiClient for Linux from the official Fortinet support portal (support.fortinet.com) after authenticating.
- 5. Uninstall the current FortiClient version using the package manager (e.g., 'apt remove forticlient' or 'rpm -e forticlient').
- 6. Install the new package for the fixed version (7.0.3 or later).
- 7. Verify the installation by checking the version number and ensuring FortiClient runs without errors.
- 8. Review FortiClient configuration and logs to confirm the permission issue is resolved.
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Forticlient
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-44167 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-44167 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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