Fortinet FortiWLC up to 8.6.0 Web Interface cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Fortinet FortiWLC up to 8.3.3/8.4.2/8.4.8/8.5.3/8.6.0. It has been classified as problematic. This impacts an unknown function of the component Web Interface. Performing a manipulation results in cross site scripting. This vulnerability was named CVE-2021-26087. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Fortinet FortiWLC up to 8.3.3/8.4.2/8.4.8/8.5.3/8.6.0. It has been classified as problematic. This affects an unknown code block of the component Web Interface. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

An improper neutralization of input during web page generation in FortiWLC version 8.6.0, version 8.5.3 and below, version 8.4.8 and below, version 8.3.3 web interface may allow both authenticated remote attackers and non-authenticated attackers in the same network as the appliance to perform a stored cross site scripting attack (XSS) via injecting malicious payloads in different locations.

The advisory is shared at fortiguard.fortinet.com. This vulnerability is uniquely identified as CVE-2021-26087 since 01/25/2021. The exploitability is told to be easy. It is possible to initiate the attack remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.6

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CNA Base Score: 4.3
CNA Vector (fortinet): 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/25/2021 🔍
03/17/2025 +1512 days 🔍
03/17/2025 +0 days 🔍
07/25/2025 +129 days 🔍

Sourcesinfo

Vendor: fortinet.com

Advisory: FG-IR-20-137
Status: Confirmed

CVE: CVE-2021-26087 (🔍)
GCVE (CVE): GCVE-0-2021-26087
GCVE (VulDB): GCVE-100-299913

Entryinfo

Created: 03/17/2025 14:47
Updated: 07/25/2025 01:08
Changes: 03/17/2025 14:47 (64), 07/25/2025 01:08 (12)
Complete: 🔍
Cache ID: 216::103

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