CVE-2021-3384

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-02 · updated 2026-06-17

Description

A vulnerability in Stormshield Network Security could allow an attacker to trigger a protection related to ARP/NDP tables management, which would temporarily prevent the system to contact new hosts via IPv4 or IPv6. This affects versions 2.0.0 to 2.7.7, 2.8.0 to 2.16.0, 3.0.0 to 3.7.16, 3.8.0 to 3.11.4, and 4.0.0 to 4.1.5. Fixed in versions 2.7.8, 3.7.17, 3.11.5, and 4.2.0.

Affected products

Stormshield Network Security: from 2.0.0 before 2.7.8; from 2.8.0 through 2.16.0; from 3.0.0 through 3.7.17; from 3.8.0 through 3.11.5; from 4.0.0 before 4.1.5 — fixed in 2.7.8, 4.1.5

How to fix

Upgrade to a fixed version: Stormshield Network Security 2.7.8, 4.1.5. Check the vendor advisory for mitigations.

References

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