Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:A) | Adjacent network |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Broadcom Brocade Active Support Connectivity Gateway
CVE-2026-85421 affects Broadcom Brocade Active Support Connectivity Gateway, a product from Broadcom. Before acting, confirm where Broadcom Brocade Active Support Connectivity Gateway runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: A critical security vulnerability has been identified in Brocade ASCG versions before 3.5.0. The HTTPS service fails to properly enforce authentication or access control checks on incoming requests. An unauthenticated attacker with network access can issue control commands, alter cluster states, and modify system configurations, leading to a complete compromise of the streaming service control plane.
The weakness class is Missing Authentication. A critical function can be used without logging in.
Based on its CVSS vector, the flaw needs local or adjacent access, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Broadcom Brocade Active Support Connectivity Gateway |
| Affected versions | Brocade Active Support Connectivity Gateway before 3.5.0 |
| Published | Oct 8, 2026 |
| Last modified | Oct 14, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | sirt@brocade.com |
How to detect it
- Inventory every instance of Broadcom Brocade Active Support Connectivity Gateway and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Broadcom Brocade Active Support Connectivity Gateway named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Broadcom Brocade Active Support Connectivity Gateway to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-306: Missing Authentication More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
In Brocade ASCG before 3.5.0, a local unauthorized user on the ASCG VM who can issue a request to the SANnav host network namespace can extract stored management credentials for onboarded SANnav instances and compromise connected Brocade SANnav servers or managed Brocade Fibre Channel switches.
A vulnerability in the SupportLink API authentication component of Brocade ASCG versions prior to 3.5.0 allows an attacker to bypass authentication across deployments due to the use of a hard coded cryptographic key.
When Brocade ASCG before 3.5.0 processes support bundle archives ingested from remote compromised endpoints, the application fails to sanitize path traversal sequences contained within archive entries prior to extraction. An unauthenticated remote attacker capable of sending or intercepting ingested archive files can leverage this flaw to write arbitrary files to restricted locations on the underlying host, potentially leading to remote code execution.
An authentication flaw exists in the Brocade ASCG administrative management service component. An unauthenticated network user can issue direct API requests to perform privileged actions, including accessing sensitive system configuration mapping data, modifying managed device inventories, and altering operational settings. This vulnerability affects all versions of Brocade ASCG before 3.5.0.
Brocade ASCG before 3.5.0 has a well-known Brocade default password embedded in a script distributed to every customer. Any local authenticated user with read access to the installation path can discover this credential and perform privilege escalation on affected Open Virtual Appliance (OVA) deployments, where default configuration settings remain in place.
A path traversal vulnerability exists in the HTTP service component of Brocade ASCG versions before 3.5.0. An unauthenticated attacker on the local network could send a manipulated API request to the service endpoint bypassing path restrictions to arbitrary file read, file write, or file deletion operations.
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