---
id: CVE-2026-80989
title: 'net: thunderbolt: Mark the connection down when bringing it up fails'
summary: |-
  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 logi…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-1341
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e <
    e0d4a17afde5aa0045dc3e1d66c6bb80927bad8c
  - >-
    Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e <
    ed1d6e3d735e7b03f43a02f4306c89eb7663da14
  - >-
    Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e <
    f01e6a35c440b62f060e21f36b385e574a7f308c
  - >-
    Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e <
    d6c0af293129345a17dc31c9b4179dc7f3d6af7a
  - >-
    Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e <
    3c8b26ebf525ba5960510f48c6e9936a79ebe76f
  - Linux 4.15
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T19:21:56.534569Z'
published: '2026-09-11'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T08:46:13.533Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-80989'
references:
  - url: 'https://git.kernel.org/stable/c/e0d4a17afde5aa0045dc3e1d66c6bb80927bad8c'
  - url: 'https://git.kernel.org/stable/c/ed1d6e3d735e7b03f43a02f4306c89eb7663da14'
  - url: 'https://git.kernel.org/stable/c/f01e6a35c440b62f060e21f36b385e574a7f308c'
  - url: 'https://git.kernel.org/stable/c/d6c0af293129345a17dc31c9b4179dc7f3d6af7a'
  - url: 'https://git.kernel.org/stable/c/3c8b26ebf525ba5960510f48c6e9936a79ebe76f'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80989.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80989'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532453'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80989'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80989'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80989.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00343
epssPercentile: 0.2761
scores:
  cna: 8.8
  vendor: 7
ingestedAt: '2026-09-14T15:23:07.454Z'
---

## Overview

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.

## Affected

- `Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e < e0d4a17afde5aa0045dc3e1d66c6bb80927bad8c`
- `Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e < ed1d6e3d735e7b03f43a02f4306c89eb7663da14`
- `Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e < f01e6a35c440b62f060e21f36b385e574a7f308c`
- `Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e < d6c0af293129345a17dc31c9b4179dc7f3d6af7a`
- `Linux >= e69b6c02b4c3b8d03be7136f90dd9551ad5a5a5e < 3c8b26ebf525ba5960510f48c6e9936a79ebe76f`
- `Linux 4.15`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80989.json)