NULL pointer dereference in Linux kernel cdns3 USB driver PCI probe
Key facts
- Attack vector
- —
- Privileges required
- —
- User interaction
- —
- Attack complexity
- —
- Impact type
- —
- Confidentiality · integrity · availability
- —
- Fix status
- Partial Red Hat: 1 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
The cdns3 USB driver for the Cadence USBSS controller in the Linux kernel has a NULL pointer dereference in cdns3_pci_probe. When the second PCI function is probed before the first has set its driver data, the driver dereferences a NULL pointer and crashes the kernel. The fix makes the probe return -EPROBE_DEFER so that probing is retried after the first function completes.
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: usb: cdns3: Fix NULL pointer dereference in cdns3_pci_probe The Cadence USBSS controller is a two-function PCI device. The first probed function allocates the driver data and stores it with pci_set_drvdata(), while the second function reuses it via pci_get_drvdata() when pci_is_enabled() reports that the first function has already been probed. When the second function is probed while the first one has been enabled but has not yet set its driver data, pci_get_drvdata() returns NULL, and the subsequent wrap->devfn assignment dereferences a NULL pointer and crashes the kernel. logs: Call trace: cdns3_pci_probe+0xa4/0x300 local_pci_probe+0x44/0xa8 pci_call_probe+0x54/0x158 pci_device_probe+0x84/0x100 really_probe+0x184/0x3d0 __driver_probe_device+0x80/0x178 driver_probe_device+0x44/0xe8 __driver_attach+0xec/0x1f8 bus_for_each_dev+0x7c/0xe0 driver_attach+0x28/0x38 bus_add_driver+0x110/0x238 driver_register+0x64/0x128 __pci_register_driver+0x50/0x60 cdns3_pci_driver_init+0x28/0x38 do_one_initcall+0x5c/0x280 do_initcalls+0x104/0x1d8 kernel_init_freeable+0x140/0x218 kernel_init+0x28/0x1f8 ret_from_fork+0x10/0x20 Return -EPROBE_DEFER in this case so that probing is retried after the first function has completed its probe.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Linux kernel fixed versions are 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10 and 7.3. Red Hat lists Red Hat Enterprise Linux 10 as affected without a fix and its plan is none available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA Linux (Linux) Fixed in 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.113, 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 |
Not affected: 6 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
- Red Hat OpenShift Container Platform 5
Timeline
- 2026-10-18 Threatist record created from CVE-2026-98756
- 2026-10-18 Alias added: GHSA-r25x-m228-w665
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@dbdd0ca9a7eac140697a366f698a0e2bb02a06a1 · CNA
- 2026-10-21 1 new reference · CNA
- 2026-10-23 Affected versions changed · Red Hat
- 2026-10-23 CVSS score added · Red Hat
- 2026-10-30 Fix available: Linux/Linux@399b18b18f54495eeeda8d88e039e6af27d020c9, Linux/[email protected], Linux/[email protected] +3 · CNA
- 2026-10-30 3 new references · CNA
- 2026-11-06 Affected versions changed · Red Hat
References
Other 8
- https://git.kernel.org/stable/c/399b18b18f54495eeeda8d88e039e6af27d020c9
- https://git.kernel.org/stable/c/88b473800ae11397e2e169aff2e17b041c040409
- https://git.kernel.org/stable/c/fc13243658da9ed3c4c94aaff77c36a10f441b89
- https://git.kernel.org/stable/c/dbdd0ca9a7eac140697a366f698a0e2bb02a06a1
- https://git.kernel.org/stable/c/549c04df02f1bb5a10342f32e2c87f5d27c97279
- https://git.kernel.org/stable/c/d16046f1ace2691b6a946f022fe6dc215936880b
- https://git.kernel.org/stable/c/45b606418bae73c7cde9f0e57e5b0977c816a7c0
- https://git.kernel.org/stable/c/e5052f2c5c73c1dcca42bafc0bc737af2b2af059
More Linux vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- 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-2026-98756 · CVE Program
- CVE-2026-98756 · NVD
- FIRST EPSS
- GHSA-r25x-m228-w665 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-98756 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences