CVE-2026-56854

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/797040
https://go.dev/issue/80213
https://pkg.go.dev/vuln/GO-2026-6303

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 16:18

Updated : 2026-09-03 16:37

NVD link : CVE-2026-56854

Mitre link : CVE-2026-56854

CVE.ORG link : CVE-2026-56854

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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