Answer Brief
CISA has warned of active exploitation of CVE-2025-67038, a critical code injection vulnerability in Lantronix EDS5000 Series devices, requiring Federal Civilian Executive Branch agencies to apply patches by June 26, 2026. The flaw allows unauthenticated remote command execution with root privileges via the HTTP RPC module, posing significant risks to network integrity and device security.
Signal Timeline
A quick visual path for analysts before reading the full brief.
- 1
Forescout Research Vedere Labs disclosed CVE-2025-67038 as part of the BRIDGE:BREAK vulnerability set affecting Lantronix and Silex serial-to-IP converters
- 2
CISA issued warning of active exploitation and urged FCEB agencies to patch by June 26, 2026
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Deadline for FCEB agencies to apply fixes for CVE-2025-67038
Executive Summary: CISA has warned of active exploitation of CVE-2025-67038, a critical code injection vulnerability in Lantronix EDS5000 Series devices, requiring Federal Civilian Executive Branch agencies to apply patches by June 26, 2026. The flaw allows unauthenticated remote command execution with root privileges via the HTTP RPC module, posing significant risks to network integrity and device security.
Why It Matters
CISA’s warning regarding active exploitation of CVE-2025-67038 in Lantronix EDS5000 Series devices underscores a critical risk to network edge infrastructure, particularly in environments where serial-to-IP converters are deployed for industrial, operational, or remote access purposes. The vulnerability resides in the HTTP RPC module, where insufficient input validation during authentication failure handling allows unauthenticated remote attackers to execute arbitrary commands with root privileges by manipulating the username field. This flaw represents a classic command injection vector, elevated by the device’s privileged execution context and frequent deployment in trusted network segments. Disclosed in April 2026 by Forescout Research Vedere Labs as part of the BRIDGE:BREAK series—which examined security weaknesses in serial-to-IP converters from Lantronix and Silex—the vulnerability has now moved from theoretical risk to active exploitation, though CISA has not attributed the activity to any specific threat actor or campaign. The urgency of the June 26, 2026 patch deadline for FCEB agencies reflects the severity of the threat, especially given the potential for full system compromise, data exfiltration, lateral movement, and disruption of device functionality. Because Lantronix EDS5000 devices often operate with elevated privileges and are embedded in critical network paths—such as those connecting serial equipment to IP networks in manufacturing, energy, or transportation sectors—their compromise could serve as a foothold for broader network intrusion. The absence of authentication requirements for exploitation increases the attack surface, particularly if devices are exposed to untrusted networks or lack proper network segmentation. This alert aligns with a broader pattern of increased targeting of network infrastructure and edge devices, as evidenced by concurrent warnings about Ubiquiti UniFi OS vulnerabilities (CVE-2026-34908 through CVE-2026-34910), which also allow remote code execution and have been chaining to achieve full system control. The temporal proximity of these advisories suggests attackers may be shifting focus toward legacy and embedded systems that often lack robust security controls, regular patching cycles, or endpoint detection capabilities. Security teams should treat this not as an isolated incident but as a signal to reassess asset inventories for similar serial-to-IP converters, audit management interface exposure, and validate patch levels across embedded systems. Operational implications extend beyond immediate patching. Organizations must verify whether Lantronix EDS5000 devices are internet-facing or accessible from less-trusted zones, review logs for anomalous command execution patterns, and consider compensating controls such as web application firewalls (WAFs) or API gateways to sanitize input before it reaches vulnerable modules. Where patching cannot be implemented immediately, isolating affected devices and restricting access to known legitimate sources are critical interim steps. The incident also highlights persistent challenges in securing embedded and legacy systems, which frequently run outdated software, lack memory protections, and are excluded from enterprise vulnerability management programs. As these devices increasingly converge with IT and OT networks, their security posture becomes integral to overall organizational resilience. Continuous monitoring, asset discovery, and supply chain awareness—particularly for third-party components in industrial equipment—are essential to mitigate similar risks. Looking ahead, security teams should monitor for further disclosures in the BRIDGE:BREAK set, track any evidence of exploitation in threat intelligence feeds, and assess whether similar flaws exist in comparable serial-to-IP solutions from other vendors. Validation of patch efficacy, confirmation of reboot requirements, and verification of service restoration post-update should be part of the remediation process. Ultimately, this event reinforces the necessity of treating edge devices with the same rigor as traditional IT assets in vulnerability management and threat monitoring programs.
Event Type: security
Importance: high
Affected Companies
- CISA
- Forescout Research Vedere Labs
- Lantronix
- Ubiquiti
Affected Sectors
- embedded systems
- industrial control systems
- network security
Key Numbers
- CVSS score: 9.8
- Patch deadline for FCEB agencies: June 26, 2026
- Vulnerability disclosed: April 2026
Timeline
- Forescout Research Vedere Labs disclosed CVE-2025-67038 as part of the BRIDGE:BREAK vulnerability set affecting Lantronix and Silex serial-to-IP converters
- CISA issued warning of active exploitation and urged FCEB agencies to patch by June 26, 2026
- Deadline for FCEB agencies to apply fixes for CVE-2025-67038
Frequently Asked Questions
What is CVE-2025-67038 and why is it critical?
CVE-2025-67038 is a code injection flaw in Lantronix EDS5000 Series devices with a CVSS score of 9.8. It allows unauthenticated attackers to inject arbitrary OS commands via the username parameter in the HTTP RPC module, leading to root-level command execution.
Who is affected by the active exploitation of this flaw?
Federal Civilian Executive Branch (FCEB) agencies are specifically urged to patch by June 26, 2026. However, any organization using Lantronix EDS5000 Series devices is at risk due to active exploitation in the wild.
What is the BRIDGE:BREAK vulnerability set?
BRIDGE:BREAK is a codename for a broader set of vulnerabilities disclosed by Forescout Research Vedere Labs in April 2026 that impacted serial-to-IP converters from Lantronix and Silex, of which CVE-2025-67038 is a part.
How does the vulnerability in the HTTP RPC module allow command injection?
The HTTP RPC module executes a shell command to write logs when user authentication fails. The username is directly concatenated with the command without sanitization, allowing attackers to inject arbitrary OS commands into the username parameter, which are then executed with root privileges.
What mitigations should organizations apply if patching is delayed?
Organizations should implement network segmentation, enforce least-privilege access controls, monitor for unusual command execution or unexpected network connections, and deploy intrusion detection systems to detect command injection attempts targeting the HTTP RPC module.