Vulnerability · Published Sep 25, 2026 · Assigned by Ciena
CVE-2026-5267Unauthenticated Event Stream Exposure of Session Tokens in Navigator NCS
High 7.5
In plain English
A high-severity missing authentication in Navigator NCS from Ciena. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 70.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Ciena | Navigator NCS | 7.2 and any older release7.2-P01 through 7.2-P078.08.0-P01 through 8.0-P06A8.18.1-P01 through 8.1-P068.28.2-P01 through 8.2-P06 |
Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N