CVE-2026-56854 (GCVE-0-2026-56854)
Vulnerability from cvelistv5
Published
2026-08-28 15:14
Modified
2026-08-28 20:17
Summary
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.
Impacted products
Show details on NVD website


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              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
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                "timestamp": "2026-08-28T20:16:07.248758Z",
                "version": "2.0.3"
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          "packageName": "golang.org/x/crypto/ssh",
          "product": "golang.org/x/crypto/ssh",
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            },
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              "version": "0",
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          "value": "Longwei Wang (@gn00295120)"
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        }
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      "title": "Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh"
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    "dateReserved": "2026-06-23T15:10:49.353Z",
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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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