CVE-2021-26102Public exploitNetwork attack vector

Unauthenticated file deletion via POST path traversal

Published Dec 19, 2024 · Updated Dec 19, 2024

Path traversal in Fortinet FortiWAN 4.4.0 through 4.4.1 and 4.5.0 through 4.5.7 allows remote attackers to delete system files. A crafted POST request supplies a relative path that escapes its intended directory, allowing the targeted file to be removed. No authentication is required, and deleting specific configuration files resets the administrator password to its default value.

CVSS severity9.8
Critical
EPSS probability16.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Fortinet FortiWAN 4.4.0 through 4.4.1 and 4.5.0 through 4.5.7 allows remote attackers to delete system files. A crafted POST request supplies a relative path that escapes its intended directory, allowing the targeted file to be removed. No authentication is required, and deleting specific configuration files resets the administrator password to its default value.

The record

CVE
CVE-2021-26102
Published
Dec 19, 2024
Updated
Dec 19, 2024
Vendor
Fortinet
Product
FortiWAN
Classifications
CWE-305, CWE-22, T1485, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 19, 2024CVE publishedPublication date reported by the CVE source.
  2. Dec 19, 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=4.4.0 <=4.4.1
  2. Affected versionversion=4.5.0 <=4.5.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiWANversion=4.4.0 <=4.4.1; version=4.5.0 <=4.5.7

Published CVSS scores

9.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
9.8Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:N/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 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 exploitPublished

Weakness, pattern, technique

CWE-305Authentication Bypass by Primary Weakness
CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1485Data Destruction
T1190Exploit Public-Facing Application

Public exploit references

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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