Unauthenticated Event Stream Exposure of Session Tokens in Navigator NCS (CVE-2026-5267) | HOL Guard CVE

High · CVSS 7.5CVE-2026-5267

Unauthenticated Event Stream Exposure of Session Tokens in Navigator NCS

Answer in brief

CVE-2026-5267 records a High severity (CVSS 7.5) vulnerability in Unauthenticated Event Stream Exposure of Session Tokens in Navigator NCS. The current sources do not mark it as known exploited. The current feed maps Ciena/Navigator NCS (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 25, 2026Updated Sep 25, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 25, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Ciena/Navigator NCS (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Ciena/Navigator NCSgeneric	7.2 and any older release \|\| 7.2-P01 through 7.2-P07 \|\| 8.0 \|\| 8.0-P01 through 8.0-P06A \|\| 8.1 \|\| 8.1-P01 through 8.1-P06 \|\| 8.2 \|\| 8.2-P01 through 8.2-P06 \|\| 9.0 \|\| 9.0-P01 through 9.0-P05A \|\| 9.1 \|\| 9.1-P01 through 9.1-P05 \|\| 9.2 \|\| 9.2-P01 through 9.2-P02 \|\| 10.0 \|\| 10.0-P01 through 10.0-P01B	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Ciena/Navigator NCS.
Review the reported fix. Source-reported solution: Ciena recommends upgrading to the latest available remediated release. For additional details, refer to myciena.com for current software versions, fixes, and security advisories. Remediation and Fixes: Products Remediated Version Navigator NCS 8.0-P06B and later 8.1-P06A and later 8.2-P07 and later 9.0-P05B and later 9.1-P05A and later 9.2-P02A and later 10.0-P01C and later

Evidence timeline and material changes

Published upstream
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 25, 2026

Sources and claim methodology

Source referenceciena.com

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.