Vulnerability in Ciena Mcp

CVE-2026-5269

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.

EPSS: 0.005 (39.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5269?
CVE-2026-5269 is a critical-severity vulnerability in Ciena Mcp, classified under CWE-1393. CVSS score: 9.8/10. Published 2026-07-14.
How severe is CVE-2026-5269?
Critical severity. CVSS v3 base score is 9.8 out of 10.