High severity · published Sep 11, 2026
CVE-2026-80989
net: thunderbolt: Mark the connection down when bringing it up fails
8.8
CVSS
0.3%
EPSS
No
On KEV
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: the logout request in
that block is no longer sent, and the peer's next login request now
re-queues our login work rather than connected_work, giving the
connection a fresh login instead of a retry on stale state.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e before e0d4a17afde5aa0045dc3e1d66c6bb80927bad8c; e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e before ed1d6e3d735e7b03f43a02f4306c89eb7663da14; e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e before f01e6a35c440b62f060e21f36b385e574a7f308c; e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e before d6c0af293129345a17dc31c9b4179dc7f3d6af7a; e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e before 3c8b26ebf525ba5960510f48c6e9936a79ebe76f; 4.15 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-80989
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-80989
git.kernel.org
https://git.kernel.org/stable/c/3c8b26ebf525ba5960510f48c6e9936a79ebe76f
git.kernel.org
https://git.kernel.org/stable/c/d6c0af293129345a17dc31c9b4179dc7f3d6af7a
git.kernel.org
https://git.kernel.org/stable/c/e0d4a17afde5aa0045dc3e1d66c6bb80927bad8c
git.kernel.org
https://git.kernel.org/stable/c/ed1d6e3d735e7b03f43a02f4306c89eb7663da14
git.kernel.org
https://git.kernel.org/stable/c/f01e6a35c440b62f060e21f36b385e574a7f308c
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