Vulnerabilities · 3h ago
Cyberdione Labs researcher Erica Windisch reported Oct. 25 that Tailscale SSH port forwarding could let an attacker controlling one policy-authorized device gain root access on reachable servers. Her tests used Tailscale 1.104.2 and headscale 0.29.5 in a lab, not real networks.
Tailscale SSH checks whether a device is allowed to connect rather than asking for a password or key. With forwarding enabled, an ordinary SSH session can make Tailscale’s root-running process access a system socket reserved for root, turning permitted connectivity into root access. The attacker must already control an authorized device; this is a lateral-movement risk, not an initial way into the network.
For self-hosted networks on headscale 0.29.5, forwarding cannot be disabled, so an already-compromised device may gain root on servers its SSH grants can reach. Windisch’s lab findings do not establish attacks on live networks; Tailscale had announced no fixed version at publication.
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Part of the PlainSec briefing for 2026-10-28