Brocade Fabric OS Stack Buffer Overflow in Certificate Parsing Causes DoS
Key facts
- Attack vector
- Adjacent network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.
Summary
Brocade Fabric OS versions before 10.0.1 contain a stack-based buffer overflow (CWE-121) in the security library. When the system parses an uploaded X.509 PEM certificate for management display, it does not check the length of the Authority Key Identifier (AKI) extension before copying string tokens into an internal stack buffer. An authenticated user with administrative privileges to import custom certificates can upload one with an oversized AKI extension, which crashes the management daemon and causes a denial of service. CVSS 4.0 rates the base score 6.9 (MEDIUM); CISA's SSVC data rates exploitation as none, and the vulnerability is not in CISA's KEV catalog.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
A stack-based buffer overflow vulnerability exists in the security library component of Brocade Fabric OS versions before 10.0.1. When parsing uploaded X.509 PEM certificates for management display, the system improperly validates the length of the Authority Key Identifier (AKI) extension before copying string tokens into an internal memory buffer. An authenticated user with administrative privileges to import custom certificates can supply a certificate containing an intentionally oversized AKI extension. When the system processes or renders the certificate attributes, this can trigger a stack memory corruption leading to a denial-of-service (DoS) condition by crashing the management daemon.
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, which fixes this issue.
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-2026-87676
- 2026-10-08 Alias added: GHSA-rphp-9f89-9xvx
- 2026-10-08 CISA SSVC decision points changed
- 2026-10-08 Priority changed: MEDIUM → LOW
- 2026-10-14 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-2026-87676 · CVE Program
- CVE-2026-87676 · NVD
- FIRST EPSS
- GHSA-rphp-9f89-9xvx · GitHub Advisory Database · CC BY 4.0
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