CVE-2021-43074Network attack vector

Administrative cookie decryption via improper signature verification

Published Feb 16, 2023 · Updated Oct 22, 2024

Improper signature verification in affected Fortinet products allows attackers to decrypt parts of an intercepted administrative session cookie. Fortinet has not disclosed which cookie-signature verification routine fails or how the cryptographic check is performed incorrectly. Exploitation requires access to an administrator's cookie in transit, and the published impact is limited to partial confidentiality loss.

CVSS severity4.3
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper signature verification in affected Fortinet products allows attackers to decrypt parts of an intercepted administrative session cookie. Fortinet has not disclosed which cookie-signature verification routine fails or how the cryptographic check is performed incorrectly. Exploitation requires access to an administrator's cookie in transit, and the published impact is limited to partial confidentiality loss.

The record

CVE
CVE-2021-43074
Published
Feb 16, 2023
Updated
Oct 22, 2024
Vendor
Fortinet
Product
FortiSwitch
Classifications
CWE-347, T1557
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 16, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 22, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=6.0.0 <=6.0.7
  2. Affected versionversion=6.2.0 <=6.2.7
  3. Affected versionversion=6.4.0 <=6.4.10
  4. Affected versionversion=7.0.0 <=7.0.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fortinet · FortiSwitchversion=6.0.0 <=6.0.7; version=6.2.0 <=6.2.7; version=6.4.0 <=6.4.10; version=7.0.0 <=7.0.3
Fortinet · FortiWebversion=6.0.0 <=6.0.8; version=6.1.0 <=6.1.3; version=6.2.0 <=6.2.7; version=6.3.0 <=6.3.16; version=6.4.0 <=6.4.2
Fortinet · FortiOSversion=6.0.0 <=6.0.16; version=6.2.0 <=6.2.12; version=6.4.0 <=6.4.8; version=7.0.0 <=7.0.3
Fortinet · FortiProxyversion=1.0.0 <=1.0.7; version=1.1.0 <=1.1.6; version=1.2.0 <=1.2.13; version=2.0.0 <=2.0.7; version=7.0.0 <=7.0.1

Published CVSS scores

4.3NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
4.3FortinetCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
T1557Adversary-in-the-Middle

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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