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CVE-2026-56854 (GCVE-0-2026-56854)

Vulnerability from cvelistv5 – Published: 2026-08-28 15:14 – Updated: 2026-08-28 20:17
VLAI
Title
Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 20:16 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
golang.org/x/crypto golang.org/x/crypto/ssh Affected: 0 , < 0.55.0 (semver)
guessed Create a notification for this product.
Credits
Longwei Wang (@gn00295120)
Show details on NVD website
To clipboard 

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