Authorization bypass in Brocade Fabric OS REST API gateway
Key facts
- Attack vector
- Adjacent network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-290.
Summary
Brocade Fabric OS versions before 10.0.1 have an authorization flaw in the REST API gateway. The gate that guards restricted management endpoints trusts client-controlled HTTP headers, which is an authentication bypass by spoofing (CWE-290). An authenticated user with any valid REST session can spoof these headers to reach internal management endpoints. Low-privilege users can then view sensitive chassis metadata, hardware memory patrolling state and firmware integrity audit logs.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
An authorization logic vulnerability exists in the Brocade Fabric OS versions before 10.0.1 REST API gateway. The internal gate guarding restricted management endpoints relies exclusively on client-controlled HTTP headers. An authenticated user with any valid REST session can spoof these headers to gain unauthorized access to internal management endpoints. This allows low-privilege users to view sensitive chassis metadata, hardware memory patrolling state, and firmware integrity audit logs.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade Brocade Fabric OS to version 10.0.1 or later.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
- Fix · CNA Fabric OS (Brocade) Fixed in 10.0.1
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Brocade Fabric OS 10.0.1
22 records Highest priority Priority MEDIUM 4 MEDIUM, 18 LOW
Other records, highest priority first
- TI-2026-69336 OS command injection in Brocade Fabric OS management interfacePriority MEDIUM 43
- TI-2026-69334 Command injection in Brocade Fabric OS REST API management interfacePriority MEDIUM 43
- TI-2026-69348 Stack-based buffer overflow in Brocade Fabric OS SNMP daemonPriority MEDIUM 40
Timeline
- 2026-10-08 Threatist record created from CVE-2026-87670
- 2026-10-08 Alias added: GHSA-w843-992w-p4h2
- 2026-10-08 CISA SSVC decision points changed
- 2026-10-13 CVSS score added · NVD
References
More Brocade vulnerabilities
- TI-2025-01721 Code injection exposure in Fabric OS 9.1.0 through 9.1.1d6 KEVCVSS 4.0HIGH 8.6
- TI-2016-06760 Path traversal in Brocade Network Advisor versions released prior to and including 14.0.2 CVSS 3.0CRITICAL 9.8
- TI-2024-19729 hard-coded credentials in the documentation that appear as the appliance root password CVSS 3.1CRITICAL 9.8
- TI-2016-06762 Path traversal in Brocade Network Advisor versions released prior to and including 14.0.2 CVSS 3.0HIGH 7.5
- TI-2018-04739 OS command injection in Brocade Network Advisor CVSS 3.0CRITICAL 9.8
- TI-2016-06761 Path traversal in Brocade Network Advisor versions released prior to and including 14.0.2 CVSS 3.0HIGH 7.5
Sources
- CVE-2026-87670 · CVE Program
- CVE-2026-87670 · NVD
- FIRST EPSS
- GHSA-w843-992w-p4h2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences