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TI-2026-79810 Aliases CVE-2026-99017GHSA-67f9-vvv7-wpq7

Linux kernel Ghostwrite erratum skips detection in some builds

Priority LOW 30Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

The Linux kernel from 6.14 has a Kconfig dependency error in the T-Head Ghostwrite erratum for RISC-V. When ERRATA_THEAD_GHOSTWRITE is enabled but ERRATA_THEAD_MAE is not, the early boot alternatives never run, so vulnerable T-Head C9xx CPUs are reported as not affected and the mitigation is not applied. A local user with low privileges can affect confidentiality, integrity and availability, but the attack is highly complex.

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: riscv: errata: select RISCV_ALTERNATIVE_EARLY for THEAD GHOSTWRITE errata_probe_ghostwrite() only marks the CPU as vulnerable when it is called at the RISCV_ALTERNATIVES_EARLY_BOOT stage, and the mitigation in ghostwrite_enable_mitigation() only takes effect if the vulnerable state was recorded before the boot alternatives are patched. The early boot stage is only executed when CONFIG_RISCV_ALTERNATIVE_EARLY is enabled, which currently is only selected by ERRATA_THEAD_MAE. In a kernel built with ERRATA_THEAD_GHOSTWRITE=y but ERRATA_THEAD_MAE=n, the early alternatives never run, so ghostwrite_state is never set to VULNERABLE: ghostwrite_enable_mitigation() returns false, xtheadvector remains enabled, and sysfs reports "Not affected" on a vulnerable T-Head C9xx CPU. Select RISCV_ALTERNATIVE_EARLY from ERRATA_THEAD_GHOSTWRITE so that the vulnerability is detected in the early boot stage and the default mitigation is applied.

Why it matters now

EPSS 0.00163 5th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.18.57, 7.2.11, 7.3Red Hat: 1 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.14 and later6.18.57, 7.2.11, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.14 and later Fixed in 6.18.57, 7.2.11, 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

Update the Linux kernel to 6.18.57, 7.2.11 or 7.3, which fix the flaw. Red Hat Enterprise Linux 10 is affected, and Red Hat has no fix available for it.

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

  • Fix · CNA Linux (Linux) Fixed in 6.18.57, 7.2.11, 7.3

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
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

  1. 2026-10-23 Threatist record created from CVE-2026-99017
  2. 2026-10-23 Alias added: GHSA-67f9-vvv7-wpq7
  3. 2026-10-24 CVSS score added · CNA
  4. 2026-10-24 Priority changed: LOW → MEDIUM
  5. 2026-10-24 Priority changed: MEDIUM → LOW
  6. 2026-11-02 Affected versions changed · Red Hat
  7. 2026-11-02 CVSS score added · Red Hat
  8. 2026-11-03 Affected versions changed · Red Hat

References

  • 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