Round-2 convergence (codex + claude-bot): sshd enforces the group
directives against the candidate's ACTUAL membership, and the gate read
only the *Users pair — an admin outside 'AllowGroups sudo' still
reached ADMIN_OK=1, and root closed on a false proof. The gate now
resolves id -Gn and judges both group directives with the *Users
discipline: DenyGroups flags on a held-group literal or ANY
pattern/host-qualified token; AllowGroups, when set, passes only on a
literal token naming a held group (a pattern that would admit proves
nothing — over-refusing stays the safe error). id failing yields no
groups, which makes a set AllowGroups flag: fail closed there too.
Both requested regressions ride the sourced lib (unmet AllowGroups,
DenyGroups naming a held group) plus the pattern/pass cases, and grep
guards pin the shipped gate to the verdicts and to real membership.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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