CVE-2021-22127

Root code execution via malicious network name

Published Apr 6, 2022 · Updated Oct 25, 2024

Improper input validation in FortiClient Linux before 6.4.3 or 6.2.9 allows unauthenticated attackers to execute root code via a malicious network name. The network-name handling path passes attacker-controlled SSID text into an OS command without adequate neutralization. Exploitation requires a user to connect to the attacker-controlled network, after which commands execute with root privileges and can compromise confidentiality, integrity, and availability.

CVSS severity7.1
High
EPSS probability0.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in FortiClient Linux before 6.4.3 or 6.2.9 allows unauthenticated attackers to execute root code via a malicious network name. The network-name handling path passes attacker-controlled SSID text into an OS command without adequate neutralization. Exploitation requires a user to connect to the attacker-controlled network, after which commands execute with root privileges and can compromise confidentiality, integrity, and availability.

The record

CVE
CVE-2021-22127
Published
Apr 6, 2022
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiClient Linux
Classifications
CWE-78, T1059.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 6, 2022CVE 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=FortiClientLinux 6.4.2 and below, FortiClientLinux 6.2.8 and below

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Fortinet · FortiClient Linuxversion=FortiClientLinux 6.4.2 and below, FortiClientLinux 6.2.8 and below

Published CVSS scores

6.7Fortinet, Inc.CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:X/RC:X
8.0NVDCVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.9NVDAV:A/AC:M/Au:N/C:C/I:C/A:C
7.1Fortinet, Inc.CVSS:3.1/AV:A/AC:H/PR:N/UI:R/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059.004Unix Shell

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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