An issue was discovered in Stormshield SNS before 4.2.3 (when the proxy is used). An attacker can saturate the proxy connection table. This would result in the proxy denying any new connections.

The Diffie-Hellman Key Agreement Protocol allows remote attackers (from the client side) to send arbitrary numbers that are actually not public keys, and trigger expensive server-side DHE modular-exponentiation calculations, aka a D(HE)at or D(HE)ater attack. The client needs very little CPU resources and network bandwidth. The attack may be more disruptive in cases where a client can require a server to select its largest supported key size. The basic attack scenario is that the client must claim that it can only communicate with DHE, and the server must be configured to allow DHE.

An issue was discovered in Stormshield SNS through 4.2.1. A brute-force attack can occur.

Stormshield SNS with versions before 3.7.18, 3.11.6 and 4.1.6 has a memory-management defect in the SNMP plugin that can lead to excessive consumption of memory and CPU resources, and possibly a denial of service.

The ClamAV Engine (version 0.103.1 and below) component embedded in Storsmshield Network Security (SNS) is subject to DoS in case of parsing of malformed png files. This affect Netasq versions 9.1.0 to 9.1.11 and SNS versions 1.0.0 to 4.2.0. This issue is fixed in SNS 3.7.19, 3.11.7 and 4.2.1.

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.

The L2TP implementation of MPD before 5.9 allows a remote attacker who can send specifically crafted L2TP control packet with AVP Q.931 Cause Code to execute arbitrary code or cause a denial of service (memory corruption).

The PPP implementation of MPD before 5.9 allows a remote attacker who can send specifically crafted PPP authentication message to cause the daemon to read beyond allocated memory buffer, which would result in a denial of service condition.

Stormshield Network Security 310 3.7.10 devices have an auth/lang.html?rurl= Open Redirect vulnerability on the captive portal. For example, the attacker can use rurl=//example.com instead of rurl=https://example.com in the query string.

Stormshield Network Security 2.0.0 through 2.13.0 and 3.0.0 through 3.7.1 has self-XSS in the command line interface of the SNS web server.