CVE-2026-56854 — Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh
The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, ext…
Published: 2026-08-28 · CVSS: 7.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7