CVE-2026-50043: SkyBridge OS Command Injection Vulnerability (MB-A100/MB-A110)

Technical summary

CVE-2026-50043 is an OS command injection vulnerability (CWE-78) affecting SkyBridge MB-A100 and MB-A110 appliances. The vulnerability arises from improper neutralization of special elements in OS command strings, permitting authenticated administrative users to inject and execute arbitrary commands through unvalidated input fields. The CVSS 3.0 score of 7.2 (HIGH severity) reflects network accessibility, low attack complexity, and high impact across confidentiality, integrity, and availability when exploited by a high-privilege account.

Business impact

Compromised SkyBridge devices could become a lateral movement vector within network infrastructure. Administrative account compromise—whether through credential theft, insider threat, or multi-stage attack—could lead to full device takeover, data exfiltration, system manipulation, and disruption of bridging/connectivity services that the appliance provides. Depending on deployment context, this could affect secure communications, network segmentation, or remote access pathways.

Affected systems

SkyBridge MB-A100 and MB-A110 devices are confirmed affected. All versions should be considered at risk unless a vendor patch explicitly indicates otherwise; verify the latest advisory from the vendor for patched versions and scope of affected releases.

Exploitability

Exploitation requires valid administrative credentials and network access to the device. While the barrier to entry is high—an attacker must first authenticate as an admin—once inside, the vulnerability is straightforward to trigger and offers no additional user interaction or complex conditions. The attack is not currently listed on CISA's Known Exploited Vulnerabilities (KEV) catalog, though organizations should monitor for proof-of-concept disclosure or real-world activity.

Remediation

Apply a vendor-issued security patch as soon as one becomes available. Until patching is feasible, enforce strict administrative access controls: restrict administrative account creation, enforce strong authentication (multi-factor authentication if supported), limit network accessibility to the device's management interface, and monitor administrative session logs for anomalous activity or command execution patterns.

Patch guidance

Contact SkyBridge or consult the vendor advisory for patched firmware versions for the MB-A100 and MB-A110. Apply patches to production devices in a controlled maintenance window, verifying functionality post-deployment. Document baseline configurations before patching to ease rollback if needed. Prioritize devices with higher network exposure or those serving critical bridging functions.

Detection guidance

Monitor SkyBridge administrative logs for unusual OS command execution, particularly commands spawned from web interfaces, API endpoints, or configuration management functions. Search logs for shell metacharacters (pipes, semicolons, backticks, command substitution syntax) in administrative input fields. Network IDS/IPS rules targeting command injection payloads may yield false positives on these appliances; tune detection to the device's normal command grammar. Correlate administrative login events with subsequent system-level process execution.

Why prioritize this

Although exploitation requires high privileges, admin account compromise is a realistic post-breach scenario in many networks. The vulnerability grants full OS-level code execution, enabling lateral movement, data theft, and persistent backdoors. Early patching limits the window of opportunity for attackers who have already breached the perimeter or gained temporary admin access through phishing or credential stuffing.

Risk score, explained

A CVSS 3.0 score of 7.2 reflects network-based attack surface, low complexity, and severe impact (all C/I/A high). The requirement for high-privilege authentication (PR:H) prevents widespread unauthenticated exploitation but does not substantially lower risk, as administrative credentials are frequently targeted in post-compromise activity. The HIGH severity rating appropriately captures the criticality of this vector for users deploying SkyBridge in security-sensitive roles.

Frequently asked questions