CVE-2020-15940Network attack vector

Cross-site scripting via unsanitized name parameters

Published Nov 2, 2021 · Updated Oct 25, 2024

Stored cross-site scripting in Fortinet FortiClient EMS 6.4.1 and earlier allows remote authenticated users to inject script through name fields. Various server sections accept the name parameter without neutralizing script or tag content before web-page generation; Fortinet does not identify the affected handlers. Exploitation requires authenticated access and user interaction, allowing injected content to modify data in another security scope.

CVSS severity4.1
Medium
EPSS probability0.73%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Fortinet FortiClient EMS 6.4.1 and earlier allows remote authenticated users to inject script through name fields. Various server sections accept the name parameter without neutralizing script or tag content before web-page generation; Fortinet does not identify the affected handlers. Exploitation requires authenticated access and user interaction, allowing injected content to modify data in another security scope.

The record

CVE
CVE-2020-15940
Published
Nov 2, 2021
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiClient EMS
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 2, 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

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=FortiClientEMS 6.4.1, 6.4.0, 6.2.9, 6.2.8, 6.2.7, 6.2.6, 6.2.4, 6.2.3, 6.2.2, 6.2.1, 6.2.0, 6.0.8, 6.0.6, 6.0.5, 6.0.4, 6.0.3, 6.0.2, 6.0.1, 6.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fortinet · FortiClient EMSversion=FortiClientEMS 6.4.1, 6.4.0, 6.2.9, 6.2.8, 6.2.7, 6.2.6, 6.2.4, 6.2.3, 6.2.2, 6.2.1, 6.2.0, 6.0.8, 6.0.6, 6.0.5, 6.0.4, 6.0.3, 6.0.2, 6.0.1, 6.0.0

Published CVSS scores

4.1FortinetCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
4.0FortinetCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N/E:F/RL:X/RC:X

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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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