CVE-2026-5269Network attack vector

Hidden account access via predictable default passwords

Published Jul 14, 2026 · Updated Jul 14, 2026

Default passwords in Ciena Navigator NCS, MCP, and PlannerPlus allow remote attackers to access hidden internal system accounts. Internal software-operation accounts are shipped with predictable default passwords, but Ciena has not disclosed their names or authentication endpoints. The accounts have limited standalone permissions; privilege escalation requires chaining their access with another weakness, so account access alone does not establish full control.

CVSS severity9.8
Critical
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Default passwords in Ciena Navigator NCS, MCP, and PlannerPlus allow remote attackers to access hidden internal system accounts. Internal software-operation accounts are shipped with predictable default passwords, but Ciena has not disclosed their names or authentication endpoints. The accounts have limited standalone permissions; privilege escalation requires chaining their access with another weakness, so account access alone does not establish full control.

The record

CVE
CVE-2026-5269
Published
Jul 14, 2026
Updated
Jul 14, 2026
Vendor
Ciena
Product
PlannerPlus
Classifications
CWE-1393, T1078.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 14, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=<= 4.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ciena · PlannerPlusversion=<= 4.1
Ciena · Navigator Network Control Suiteversion=<= 8.0; version=8.1

Published CVSS scores

9.8INCIBE-CERTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1393Use of Default Password
T1078.001Default Accounts

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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