CVE-2021-26108Network attack vector

SSL-VPN key disclosure via hard-coded firmware secret

Published Dec 8, 2021 · Updated Oct 25, 2024

Hard-coded cryptographic key use in Fortinet FortiOS before 7.0.1 allows remote attackers to retrieve an SSL-VPN key. The SSL-VPN component embeds a cryptographic key in firmware in a form recoverable through reverse engineering. Exploitation requires no authentication or user interaction, and the reported consequence is limited to disclosure of the embedded key.

CVSS severity7.5
High
EPSS probability1.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hard-coded cryptographic key use in Fortinet FortiOS before 7.0.1 allows remote attackers to retrieve an SSL-VPN key. The SSL-VPN component embeds a cryptographic key in firmware in a form recoverable through reverse engineering. Exploitation requires no authentication or user interaction, and the reported consequence is limited to disclosure of the embedded key.

The record

CVE
CVE-2021-26108
Published
Dec 8, 2021
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiOS
Classifications
CWE-798
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 8, 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=FortiOS before 7.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiOSversion=FortiOS before 7.0.1

Published CVSS scores

7.5Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST National Vulnerability DatabaseAV:N/AC:L/Au:N/C:P/I:N/A:N

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials

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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