Use of torn-down DP tunnel in Linux kernel Thunderbolt driver
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- Partial Red Hat: 4 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
The Linux kernel from 6.14 contains a flaw in the thunderbolt driver where a DP tunnel is accessed after its DPRX read was canceled. A cancellation that arrives while the work is already running is missed, so the driver polls DPRX capabilities and runs a callback for a tunnel that was already torn down while the domain was suspending or going away.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
In the Linux kernel, the following vulnerability has been resolved: thunderbolt: Don't access a DP tunnel after its DPRX read was canceled tb_dp_dprx_work() checks ->dprx_canceled before it takes tb->lock so it misses a tb_dp_dprx_stop() that could not cancel the already running work. It then polls the DPRX capabilities and runs the callback for a tunnel that has already been torn down while the domain is suspending or going away. This can be hit by cancelling the DPRX read from outside the ordered tb->wq: During suspend tb_disconnect_and_release_dp() does just this and with a later patch tb_stop() will do it as well. The latter in combination with the Apple NHI where the DPRX read never completed is how I hit this. Check the flag with tb->lock held instead and check it again in tb_dp_tunnel_active() because the callback runs after the lock has been dropped again. Also clear the flag in tb_dp_dprx_start() so that it only ever describes the work that is currently in flight.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
The Linux kernel is fixed in 6.18.56, 7.2.10 and 7.3. Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 and Red Hat OpenShift Container Platform 5 are affected without a fix, and Red Hat's plan for them is none available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA Linux (Linux) Fixed in 6.18.56, 7.2.10, 7.3
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
Not affected: 5 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
Timeline
- 2026-10-18 Threatist record created from CVE-2026-98689
- 2026-10-18 Alias added: GHSA-8x4h-8gwm-w6jp
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-23 Affected versions changed · Red Hat
- 2026-10-23 CVSS score added · Red Hat
- 2026-10-30 Affected versions changed · Red Hat
References
More Linux vulnerabilities
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- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-98689 · CVE Program
- CVE-2026-98689 · NVD
- FIRST EPSS
- GHSA-8x4h-8gwm-w6jp · GitHub Advisory Database · CC BY 4.0
- CVE-2026-98689 · Red Hat security data · CC BY 4.0
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