CVE-2021-36176Network attack vector

Reflected XSS via incorrect sanitization context

Published Nov 2, 2021 · Updated Oct 25, 2024

Reflected XSS in Fortinet FortiPortal before 6.0.6 allows remote attackers to execute script in a user's browser via a crafted request. The web interface renders attacker-controlled request data in the wrong sanitization context; Fortinet has not disclosed the affected parameter or rendering path. Exploitation requires a user to open the crafted request, and the resulting script can read or modify data available to that user's FortiPortal session.

CVSS severity6.1
Medium
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Fortinet FortiPortal before 6.0.6 allows remote attackers to execute script in a user's browser via a crafted request. The web interface renders attacker-controlled request data in the wrong sanitization context; Fortinet has not disclosed the affected parameter or rendering path. Exploitation requires a user to open the crafted request, and the resulting script can read or modify data available to that user's FortiPortal session.

The record

CVE
CVE-2021-36176
Published
Nov 2, 2021
Updated
Oct 25, 2024
Vendor
Fortinet
Product
FortiPortal
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

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

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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=FortiPortal before 6.0.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiPortalversion=FortiPortal before 6.0.6

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
5.8FortinetCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:P/RL:U/RC:C
6.1FortinetCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

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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