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TI-2026-81875 Aliases CVE-2026-99168GHSA-3wc5-v6vv-97qx

NULL dereference in Linux kernel mshv_vtl register page mapping

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 Linux kernel mshv_vtl driver from 6.19 does not check whether a CPU's register page exists before mapping it. If register page setup fails on one CPU while another CPU succeeds, the driver checks a global flag instead of that CPU's page, so a userspace page fault on the missing page dereferences a NULL pointer.

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: mshv_vtl: Check per-CPU register page before mmap Register-page setup is optional for each CPU. If allocation or registration fails, mshv_vtl_configure_reg_page() warns and leaves that CPU's reg_page NULL, but initial context setup continues successfully. Meanwhile, successful setup on another CPU sets the global mshv_has_reg_page flag. mshv_vtl_fault() checks this global flag before selecting the requested CPU's register page. With mixed setup results across online CPUs, the check passes even for a CPU with no register page, reaching get_page(NULL) when userspace faults in that mapping. Check the selected per-CPU register page before taking its reference and return VM_FAULT_SIGBUS if it is absent.

Why it matters now

EPSS 0.00156 4th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 7.2.13, 7.3

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.19 and later7.2.13, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.19 and later Fixed in 7.2.13, 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

Upgrade the Linux kernel to 7.2.13 or 7.3.

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

  • Fix · CNA Linux (Linux) Fixed in 7.2.13, 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. 2026-10-28 Threatist record created from CVE-2026-99168
  2. 2026-10-28 Alias added: GHSA-3wc5-v6vv-97qx
  3. 2026-10-29 Affected versions changed · Red Hat
  4. 2026-10-29 CVSS score added · Red Hat
  5. 2026-11-06 Affected versions changed · Red Hat

References

Other 2

  • 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 21741 →

Sources

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