CVE-2026-87686: broadcom fabric_operating_system Authentication Bypass by Spoofing
Vulnerability summary
CVE-2026-87686 is a medium (CVSS 5.3) Authentication Bypass by Spoofing vulnerability in broadcom fabric_operating_system. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 6.8% of scored vulnerabilities.
Timeline
- 08-10-2026PublishedVulnerability first disclosed.
- 08-10-2026Last modifiedVulnerability information updated.
Description
An authentication and access control bypass vulnerability exists in the web server management interface of Brocade Fabric OS versions before 10.0.1. The web dispatcher routine evaluates internal management VLAN trust decisions using the client-supplied HTTP host header instead of the actual socket transport layer source IP address. Successful exploitation allows the attacker to bypass IP-filtering access control lists (ACLs) and obtain sensitive device metadata (such as model, serial number, hardware revision, and firmware version) without authentication.
CVSS metrics
3 scores · 2 sources · 2 versions- NVDNIST5.3MediumCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/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
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
7%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Broadcom1 product
- fabric_operating_system< 10.0.1
Brocade1 product
- fabric_os< 10.0.1
2 vendors · 2 products