Fabric Composer: Improper Authentication
CVE-2026-19766 is a critical-severity improper authentication vulnerability in Fabric Composer from Hewlett Packard Enterprise, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected Fabric Composer versions: 7.0.0 through 7.3.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Fabric Composer you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on support.hpe.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Hewlett Packard Enterprise | Fabric Composer | 7.0.0 through 7.3.3 | Not 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
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- 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:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (hpe.com).
Official description
An authentication bypass vulnerability exists in the underlying operating system of HPE Networking Fabric Composer. Successful exploitation could allow an unauthenticated adjacent attacker to execute arbitrary code as a privileged user on the underlying operating system, leading to complete compromise of the AFC host.
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.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Fabric Composer
- 7.1 High severity
- 7.1 High severity
- 7.4 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Improper Authentication vulnerabilities
- 7.3 High severity
- 8.1 High severity
- 7.5 High severity
- 7.1 High severity
- 10.0 Critical severity
- 10.0 Critical severity
Spotted an error? Tell us.