CVE-2021-41025Network attack vector

Unauthenticated cluster-peer impersonation via replay and race

Published Dec 8, 2021 · Updated Oct 25, 2024

Authentication bypass in Fortinet FortiWeb 6.0.0 through 6.4.1 allows remote attackers to authenticate as legitimate cluster peers. Fortinet identifies capture-replay authentication bypass and improperly synchronized concurrent use of a shared resource in confd. No credentials or user interaction are required; successful access grants the trust assigned to a cluster peer, with bounded confidentiality, integrity, and availability impact.

CVSS severity7.3
High
EPSS probability1.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Fortinet FortiWeb 6.0.0 through 6.4.1 allows remote attackers to authenticate as legitimate cluster peers. Fortinet identifies capture-replay authentication bypass and improperly synchronized concurrent use of a shared resource in confd. No credentials or user interaction are required; successful access grants the trust assigned to a cluster peer, with bounded confidentiality, integrity, and availability impact.

The record

CVE
CVE-2021-41025
Published
Dec 8, 2021
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiWeb
Classifications
CWE-362, CWE-294
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=FortiWeb 6.4.1, 6.4.0, 6.3.0 through 6.3.15, 6.2.0 through 6.2.6, 6.1.0 through 6.1.2, 6.0.0 thorugh 6.0.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiWebversion=FortiWeb 6.4.1, 6.4.0, 6.3.0 through 6.3.15, 6.2.0 through 6.2.6, 6.1.0 through 6.1.2, 6.0.0 thorugh 6.0.7

Published CVSS scores

7.3FortinetCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
6.9FortinetCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C

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-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CWE-294Authentication Bypass by Capture-replay

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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