CVE-2021-26089

Root command execution via installer symlink following

Published Jul 12, 2021 · Updated Oct 25, 2024

Improper symlink following in Fortinet FortiClient macOS 6.4.3 and earlier allows local users to execute commands as root during installation. The installer follows attacker-controlled symbolic links, allowing writable files to replace privileged shell scripts that the installer later executes. Exploitation requires low-privileged code execution on the Mac and user interaction with installation, after which attacker-supplied commands run as root.

CVSS severity6.7
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper symlink following in Fortinet FortiClient macOS 6.4.3 and earlier allows local users to execute commands as root during installation. The installer follows attacker-controlled symbolic links, allowing writable files to replace privileged shell scripts that the installer later executes. Exploitation requires low-privileged code execution on the Mac and user interaction with installation, after which attacker-supplied commands run as root.

The record

CVE
CVE-2021-26089
Published
Jul 12, 2021
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiClient macOS
Classifications
CWE-59, CWE-61, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=FortiClientMac 6.4.3 and below

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Fortinet · FortiClient macOSversion=FortiClientMac 6.4.3 and below

Published CVSS scores

6.7FortinetCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C
7.8Trend Micro Zero Day InitiativeCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-59Improper Link Resolution Before File Access ('Link Following')
CWE-61UNIX Symbolic Link (Symlink) Following
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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