CVE-2026-5269
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk19th percentile - higher than 19% of all known CVEs
Summary
In Ciena's Navigator Network Control Suite (NCS) and Manage Control Plan (MCP), hidden system accounts with default, predictable passwords were discovered. These accounts have very limited permissions but could be used by an attacker in combination with other weaknesses to escalate privileges on the system.
Risk Assessment
The risk is that an attacker could gain initial system access using a predictable password and then escalate privileges, potentially leading to full compromise of critical network infrastructure.
Recommendation
Immediately change default passwords for all hidden system accounts in NCS and MCP and enforce a strong password policy. Additionally, monitor logs for unusual login attempts on these accounts.
Other vulnerabilities in Ciena Navigator Network Control Suite
See all- CVE-2026-5270Critical
An authentication bypass vulnerability in Ciena Navigator NCS, MCP, and Blue Planet products due to improper handling of HTTP request paths and headers. An unauthenticated attacker can manipulate requests to bypass authentication and audit logging.
- CVE-2026-5267High
Ciena Navigator Network Control Suite (NCS) contains an information exposure vulnerability in an event-streaming API that does not properly enforce authentication. An unauthenticated attacker with network access to the affected service could access the event stream and potentially obtain sensitive information.
Original NVD description (English source)
In Ciena's Navigator Network Control Suite (NCS) and Manage Control Plan (MCP), there are hidden system accounts used for internal software operations. Some of these accounts have default passwords that may be predictable. While these accounts have very limited permissions on their own, an attacker could combine an attack using one of these accounts with other potential weaknesses to launch a more significant attack, possibly leading to escalation of privilege on the system.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS