CVE-2025-34236: Advantech WebAccess/VPN < 1.1.5 Stored XSS via NetworksController.addNetworkAction()

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-11-06 · updated 2026-10-07
Weakness: CWE-79

Description

Advantech WebAccess/VPN versions prior to 1.1.5 contain a stored cross-site scripting (XSS) vulnerability via NetworksController.addNetworkAction(). Insufficient validation or escaping of user-supplied input may allow an attacker to inject and execute arbitrary script in the context of a victim's browser.

Affected products

Advantech Webaccess/Vpn: before 1.1.5 — fixed in 1.1.5

How to fix

Upgrade to a fixed version: Advantech Webaccess/Vpn 1.1.5. Check the vendor advisory for mitigations.

References

https://icr.advantech.com/download/software
https://icr.advantech.com/support/router-models/download/511/sa-2025-01-vpn-portal-2025-11-06.pdf
https://www.vulncheck.com/advisories/advantech-webaccess-vpn-stored-xss-via-networkcontroller

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