5.3

CVE-2026-8474: stormshield stormshield_network_security Cross-site Scripting

CVSS: 5.3v3.1MediumDeferred
Published 01-06-2026Last modified 01-06-2026
Open JSON

Vulnerability summary

CVE-2026-8474 is a medium (CVSS 5.3) Cross-site Scripting vulnerability in stormshield stormshield_network_security. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 21.8% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.30%
0%100%
Low · +0.12 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 01-06-2026
    PublishedVulnerability first disclosed.
  2. 01-06-2026
    Last modifiedVulnerability information updated.

Description

A vulnerability was discovered on Stormshield Network Security * 4.3.0 to 4.3.41, * 4.8.0 to 4.8.15, * 5.0.0 to 5.0.5 It is possible to execute a reflected XSS attack on the login API available on Stormshield SNS appliance by executing a script on the victim's machine. The risks include the theft of cookies or other sensitive data, as well as the modification of page behavior, for example, by redirecting the victim to malicious websites.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.30%

Chance of exploitation in the next 30 days

Percentile

22%

Versus all other CVEs

30-day change

+0.12 pp

From 0.18% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.30%

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

Stormshield1 product

1 vendor · 1 product

References

1 links