CVE-2026-5267 Unauthenticated Event Stream Exposure of Session Tokens in Navigator NCS
Unauthenticated attackers can access event streams to obtain sensitive session tokens in Ciena Navigator NCS.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5267?
CVE-2026-5267 is a high-severity vulnerability in Ciena Navigator NCS, published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-306
Which versions are affected by CVE-2026-5267?
How do I fix CVE-2026-5267?
No fix has been published for CVE-2026-5267 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-5267 being exploited?
There is no known exploitation of CVE-2026-5267 in the wild and no public exploit code.
Sources
Also known as GHSA-6mqq-ppj3-rm94.