CVE-2026-5268

SFTP Server Authentication Weakness

Published Jul 6, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
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.

Remediation

Vendor 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.

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
First Time appeared Ciena
Ciena 6500 S-series
Ciena 6500 T-series
Ciena cpl
Ciena pts
Vendors & Products Ciena
Ciena 6500 S-series
Ciena 6500 T-series
Ciena cpl
Ciena pts
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title SFTP Server Authentication Weakness
Weaknesses CWE-288
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Ciena
Published
Updated
Jul 8, 2026, 8:18 PM
Reserved
Mar 31, 2026, 7:44 PM
Status
Awaiting Analysis
Published
Jul 6, 2026, 4:16 PM
Modified
Jul 8, 2026, 9:16 PM