HOMEVULNERABILITIESCVE-2021-40541
MEDIUM

CVE-2021-40541

CWE-79Published: October 11, 2021· Updated: Jun 17, 2026

6.1
CVSS v3.1

Official Description

PHPFusion 9.03.110 is affected by cross-site scripting (XSS) in the preg patterns filter html tag without "//" in descript() function An authenticated user can trigger XSS by appending "//" in the end of text.

NVD Source

Technical Analysis

CVE-2021-40541 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected Vendors & Products

php-fusion1 product(s)
phpfusion
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (2)

https://github.com/PHPFusion/PHPFusion/issues/2373Exploit · Issue Tracking · Third Party Advisory
https://github.com/PHPFusion/PHPFusion/issues/2373Exploit · Issue Tracking · Third Party Advisory

Quick Facts

CVE IDCVE-2021-40541
CVSS Score6.1 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
Affected1 vendor(s)
PublishedOct 11, 2021

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-40541 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.