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TI-2026-75893 Aliases CVE-2026-98765GHSA-84fc-mwqj-5rjh

Incomplete synchronization in Linux kernel dummy-hcd gadget driver

Priority LOW 22Published · Updated

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
Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The dummy-hcd USB gadget driver in the Linux kernel emulates synchronize_irq() without waiting for request completion handlers that are still running. A gadget driver's unbind routine can therefore run before outstanding completions finish, and its module can be unloaded while a completion handler is still executing. The source description does not state attacker requirements or exploitation.

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: gadget: dummy-hcd: Fix wait for outstanding request completions The dummy-hcd driver emulates synchronize_irq() by waiting until its private callback_usage counter drops to 0 (with the private lock not held). This counter is incremented whenever a gadget driver callback occurs (which requires the private lock to be dropped), but not when a request completion handler is called. This is an oversight. Request completion is triggered by timer interrupts (emulating device IRQs in a real UDC), and the interrupt handlers are supposed to have completed when the synchronize_irq() emulation routine returns -- they aren't supposed to be in the middle of a completion callback. If this happens it can lead to a gadget driver's unbind routine running before all outstanding request completions have finished, maybe even allowing the gadget driver's module to be unloaded while a completion handler is still running. Fix the oversight by incrementing the callback_usage value across request completion callbacks.

Why it matters now

EPSS 0.00176 7th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 3.3, 3.17, 4.2 +11

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.2.97 to before 3.3; 3.16.52 to before 3.17; 4.1.46 to before 4.2; 4.4.92 to before 4.5; 4.9.55 to before 4.10; 4.13.6 to before 4.143.3, 3.17, 4.2, 4.5, 4.10, 4.14Patch availableCNA
LinuxLinux4.14 and later5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10, 7.3Patch availableCNA
  • Linux VendorLinux Affected 3.2.97 to before 3.3; 3.16.52 to before 3.17; 4.1.46 to before 4.2; 4.4.92 to before 4.5; 4.9.55 to before 4.10; 4.13.6 to before 4.14 Fixed in 3.3, 3.17, 4.2, 4.5, 4.10, 4.14 Patch available CNA
  • Linux VendorLinux Affected 4.14 and later 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 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

The Linux kernel fixed versions are 3.3, 3.17, 4.2, 4.5, 4.10, 4.14, 5.10.273, 5.15.224, 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10 and 7.3. Some stable branches are fixed by specific commits listed in the affected ranges, so check the kernel stable tree for your branch.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 3.3, 3.17, 4.2, 4.5, 4.10, 4.14
  • 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 →

Not affected: 7 products
  • Red Hat Enterprise Linux 10
  • 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

  1. 2026-10-18 Threatist record created from CVE-2026-98765
  2. 2026-10-18 Alias added: GHSA-84fc-mwqj-5rjh
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@6849e51b89de5b6fc7447dc8e612b58df19c7dea · CNA
  5. 2026-10-21 1 new reference · CNA
  6. 2026-10-23 Affected versions changed · Red Hat
  7. 2026-10-23 CVSS score added · Red Hat
  8. 2026-10-30 Fix available: Linux/Linux@32721319e89a2be610b0518b88f0d188ce878063, Linux/Linux@48ef54100ceffbd1a055f193873574c45f408eb5, Linux/[email protected] +3 · CNA
  9. 2026-10-30 3 new references · CNA
  10. 2026-11-06 Affected versions changed · Red Hat

References

Other 8

  • 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
See all 21727 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences