CVE-2026-80989

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: thunderbolt: Mark the connection down when bringing it up fails

Every failure path in tbnet_connected_work() undoes its own work and

returns without clearing login_sent, so the connection still looks

established. The next tbnet_tear_down() therefore takes its main branch

and repeats a teardown that already happened: it stops rings that are

already stopped, which is a dev_WARN() and fatal under panic_on_warn,

and it releases net->remote_transmit_path even on the HopID mismatch

path, where this connection never owned that id, silently freeing one

that someone else is still using.

Clear login_sent on those paths. That is enough for tbnet_tear_down() to

leave the unwound state alone, and login_received has to stay set: it

records that the peer has logged in and carries the transmit path it gave

us, which nothing on this side can make the peer send again. Two things

change beyond keeping the teardown out of the way:

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References