CVE-2026-5268

CRITICALCVSS 9.1/10EPSS 0.42%

Last modified

CVE-2026-5268 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. An authentication bypass vulnerability exists in the default SFTP server component utilized across the Ciena products listed. This vulnerability allows a remote, unauthenticated attacker to bypass security controls and gain unauthorized access to the underlying filesystem. Successful exploitation could allow an attacker to read or modify system files.. EPSS estimates a 0.42% chance of exploitation in the next 30 days.

Description

An authentication bypass vulnerability exists in the default SFTP server component utilized across the Ciena products listed. This vulnerability allows a remote, unauthenticated attacker to bypass security controls and gain unauthorized access to the underlying filesystem. Successful exploitation could allow an attacker to read or modify system files.

Metrics

CVSS 3.1
9.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS Probability
0.42%

33.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
CIENA6500 S-SeriesR16.96 and prior
CIENA6500 T-SeriesR16.1 and prior
CIENAPTSR16.1 and prior
CIENACPLR12.63 and prior

References

Timeline

Published
Last Modified
Status
Awaiting Analysis

Frequently Asked Questions

What is CVE-2026-5268?
An authentication bypass vulnerability exists in the default SFTP server component utilized across the Ciena products listed. This vulnerability allows a remote, unauthenticated attacker to bypass security controls and gain unauthorized access to the underlying filesystem. Successful exploitation could allow an attacker to read or modify system files.
How severe is CVE-2026-5268?
CVE-2026-5268 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.42% probability of exploitation in the next 30 days.
How do I fix CVE-2026-5268?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

Are you affected by CVE-2026-5268?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST