CVE-2026-5268 (CVSS 9.1)

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.

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CVSS v3.1 Score

9.1

CRITICAL

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

EPSS — Exploit Prediction

0.0042

Probability of exploitation

0.34%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-288 CWE-288

References

Other References

https://www.ciena.com/product-security

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. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2026-5268? +

CVE-2026-5268 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0042, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-5268? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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