CVE-2020-9295Network attack vector

Antivirus evasion via malformed RAR inspection

Published Mar 17, 2025 · Updated Mar 17, 2025

Improper security checking in FortiClient for Windows 6.0.0 through 6.2.6 allows remote attackers to evade initial RAR archive scanning. The AV engine does not immediately detect certain malformed or non-standard RAR archives that can contain malicious files. A crafted archive must reach scanning and be opened for extraction; real-time scanning detects the contained malicious file at extraction.

CVSS severity4.7
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper security checking in FortiClient for Windows 6.0.0 through 6.2.6 allows remote attackers to evade initial RAR archive scanning. The AV engine does not immediately detect certain malformed or non-standard RAR archives that can contain malicious files. A crafted archive must reach scanning and be opened for extraction; real-time scanning detects the contained malicious file at extraction.

The record

CVE
CVE-2020-9295
Published
Mar 17, 2025
Updated
Mar 17, 2025
Vendor
Fortinet
Product
FortiClient for Windows
Classifications
CWE-358, T1027
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 17, 2025CVE publishedPublication date reported by the CVE source.
  2. Mar 17, 2025Record 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=6.0.0 <=6.0.10
  2. Affected versionversion=6.2.0 <=6.2.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiClient for Windowsversion=6.0.0 <=6.0.10; version=6.2.0 <=6.2.6

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
4.7Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/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-358Improperly Implemented Security Check for Standard
T1027Obfuscated Files or Information

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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