CVE-2026-26352

MEDIUM 5.4

Smoothwall Express < 3.1 Update 13 Stored XSS in vpnmain.cgi via VPN_IP Parameter

CVSS Score

5.4

EPSS Score

0.0%

EPSS Percentile

0th

Smoothwall Express versions prior to 3.1 Update 13 contain a stored cross-site scripting vulnerability in the /cgi-bin/vpnmain.cgi script due to improper sanitation of the VPN_IP parameter. Authenticated attackers can inject arbitrary JavaScript through VPN configuration settings that executes when the affected page is viewed by other users.

CWE	CWE-79
Vendor	smoothwall
Product	express
Published	Mar 30, 2026
Last Updated	Mar 30, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Affected Versions

Smoothwall / Express

0 ≤ 3.1 Update 13

References

NVD ↗ CVE.org ↗ EPSS Data ↗

community.smoothwall.org: https://community.smoothwall.org/forum/viewtopic.php?t=45095 vulncheck.com: https://www.vulncheck.com/advisories/smoothwall-express-stored-xss-in-vpnmain-cgi-via-vpn-ip-parameter

Credits

Alex Williams from Pellera Technologies VulnCheck