CyberSecBulletin
CVE-2026-111090NVD status: Deferred

Stormshield Network Security: Improper Authentication

CVE-2026-111090 is a high-severity improper authentication vulnerability in Stormshield Network Security from StormShield, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected Stormshield Network Security versions: 4.3.0 through 4.3.44; 4.8.0 through 4.8.19; 5.0.0 through 5.0.9, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.17% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Stormshield Network Security you run against the affected versions below, and install the vendor's latest release.
  2. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
StormshieldStormshield Network Security4.3.0 through 4.3.44; 4.8.0 through 4.8.19; 5.0.0 through 5.0.9; 5.1.0 through 5.1.3Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA (airbus.com).

Official description

A logic error exists in the signature verification routine resulting in acceptance of unauthenticated update and license files.It is necessary to use only the MyStormshield servers to retrieve update files or licenses, or to use automatic verification via SNS.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).

References

Other vulnerabilities in Stormshield Network Security

All Stormshield Network Security vulnerabilities

Recent Improper Authentication vulnerabilities

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