CVE-2026-0383: Brocade Fabric OS Information Disclosure

CVE-2026-0383 Overview

A vulnerability in Brocade Fabric OS could allow an authenticated, local attacker with privileges to access the Bash shell to access insecurely stored file contents including the history command. This information disclosure vulnerability affects storage area network (SAN) infrastructure running vulnerable versions of Brocade Fabric OS, potentially exposing sensitive configuration data, credentials, and operational commands stored in shell history files.

Critical Impact

Authenticated attackers with local Bash shell access can retrieve sensitive information from insecurely stored files, potentially leading to credential exposure, configuration disclosure, and further system compromise.

Affected Products

• Brocade Fabric OS (specific versions affected - see vendor advisory)
• Broadcom SAN Switch products running vulnerable Fabric OS versions
• Data center SAN infrastructure utilizing Brocade switches

Discovery Timeline

• 2026-02-03 - CVE CVE-2026-0383 published to NVD
• 2026-02-03 - Last updated in NVD database

Technical Details for CVE-2026-0383

Vulnerability Analysis

This vulnerability stems from insecure storage practices within Brocade Fabric OS, where sensitive file contents—including command history—are stored without adequate protection mechanisms. While the CWE classification indicates CWE-78 (OS Command Injection), the primary security concern described involves information disclosure through improperly secured file storage on the local system.

The vulnerability requires local access to the Bash shell environment, meaning an attacker must already possess valid credentials and sufficient privileges to access the command-line interface. Once authenticated, the attacker can access historical command data and other insecurely stored file contents that may contain sensitive operational information.

Root Cause

The root cause of this vulnerability lies in the insecure storage of sensitive file contents within the Brocade Fabric OS environment. Specifically, the history command functionality and related file storage mechanisms do not implement adequate access controls or encryption to protect sensitive data. This allows authenticated users with Bash shell privileges to read command history that may contain credentials, configuration changes, or other sensitive operational commands previously executed on the system.

Attack Vector

The attack vector is local, requiring the attacker to have authenticated access to the Brocade Fabric OS Bash shell environment. The exploitation chain typically involves:

1. Initial Access: The attacker gains legitimate credentials to access the Brocade switch management interface
2. Shell Access: The attacker escalates to or already possesses Bash shell access on the device
3. Information Harvesting: The attacker reads insecurely stored files, including shell history files containing previously executed commands
4. Credential/Data Extraction: Sensitive information such as passwords, configuration commands, or network topology details may be extracted from the exposed files

This vulnerability does not require complex exploitation techniques—access to the shell and standard file reading commands are sufficient to exploit the insecure storage condition. The retrieved information could facilitate lateral movement, privilege escalation, or further attacks against SAN infrastructure.

Detection Methods for CVE-2026-0383

Indicators of Compromise

• Unusual access patterns to shell history files such as .bash_history or similar files on Brocade switches
• Authentication events followed by file access operations targeting sensitive configuration or history files
• Unexpected user sessions on Brocade Fabric OS devices, particularly from unauthorized sources
• Audit logs showing repeated access to history files or sensitive directories

Detection Strategies

• Enable comprehensive audit logging on Brocade Fabric OS devices to capture all shell access and file operations
• Implement privileged access monitoring to detect and alert on shell access by non-administrative accounts
• Deploy file integrity monitoring (FIM) on sensitive directories and history files to detect unauthorized access
• Correlate authentication events with subsequent file access patterns to identify potential exploitation attempts

Monitoring Recommendations

• Review Brocade switch authentication logs regularly for unauthorized access attempts
• Monitor for suspicious command patterns that may indicate reconnaissance or data exfiltration
• Configure SIEM rules to alert on access to history files and sensitive configuration data
• Implement network segmentation monitoring to detect potential lateral movement following information disclosure

How to Mitigate CVE-2026-0383

Immediate Actions Required

• Review the Broadcom Security Advisory for specific patch and version information
• Audit all accounts with Bash shell access on Brocade Fabric OS devices and remove unnecessary privileges
• Implement strict access controls limiting shell access to only essential administrative accounts
• Review and clear shell history files containing sensitive commands on affected systems

Patch Information

Broadcom has released security advisory information for this vulnerability. Administrators should consult the Broadcom Security Advisory for specific patch versions and upgrade instructions. Apply the latest firmware updates that address insecure file storage practices in Brocade Fabric OS.

Workarounds

• Restrict Bash shell access to only essential administrative accounts and implement just-in-time privileged access
• Configure shell history settings to disable or minimize history retention using HISTSIZE=0 and HISTFILESIZE=0 environment variables
• Implement regular automated clearing of history files and ensure sensitive commands are not persisted
• Enable enhanced auditing and monitoring on all Brocade switches to detect potential exploitation attempts

# Disable shell history retention as a temporary workaround
# Add to shell profile or execute in active session
export HISTSIZE=0
export HISTFILESIZE=0

# Clear existing history file
cat /dev/null > ~/.bash_history
history -c