6.3

CVE-2025-34237: advantech webaccess\/vpn Cross-site Scripting

CVSS: 6.3v4.0MediumAnalyzed
Published 06-11-2025Last modified 17-11-2025
Open JSON

Vulnerability summary

CVE-2025-34237 is a medium (CVSS 6.3) Cross-site Scripting vulnerability in advantech webaccess\/vpn. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 11.3% of scored vulnerabilities.

Overall risk
25/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.22%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 06-11-2025
    PublishedVulnerability first disclosed.
  2. 17-11-2025
    Last modifiedVulnerability information updated.

Description

Advantech WebAccess/VPN versions prior to 1.1.5 contain a stored cross-site scripting (XSS) vulnerability via StandaloneVpnClientsController.addStandaloneVpnClientAction(). 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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.22%

Chance of exploitation in the next 30 days

Percentile

11%

Versus all other CVEs

30-day change

+0.01 pp

From 0.20% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.22%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Advantech1 product

1 vendor · 1 product

References

3 links