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TI-2026-83883 Aliases CVE-2026-99218GHSA-2cpv-4f6v-pr9h

Missing RCU locking in Linux kernel coredump thread wakeup

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: 6 without a fix

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

Summary

The Linux kernel is affected from version 2.6.27. In coredump_finish(), parked threads are released without holding RCU or a task reference, so a thread can exit and be freed before wake_up_process() runs, a use-after-free. A local user with low privileges can trigger this under high attack complexity, with high impact to confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: coredump: hold RCU while releasing parked threads coredump_finish() releases the parked threads by clearing ->task in their core_thread entry and calling wake_up_process() on each of them. It does that without holding a reference on the task and without being inside rcu. But calling wake_up_process(task) without rcu here isn't safe. A parked thread doesn't need that wakeup to leave. A spurious wakeup or a preemption after the store is enough for the task to go away. So if the coredump client is preempted between the store and wake_up_process() the thread can exit and be freed in the meantime and try_to_wake_up() takes pi_lock in freed memory. Hold rcu across the loop.

Why it matters now

EPSS 0.00122 2nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.161, 6.12.115 +4Red Hat: 6 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux2.6.27 and later6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1Patch availableCNA
  • Linux VendorLinux Affected 2.6.27 and later Fixed in 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1 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 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1 or 7.4-rc1, or to a release that includes the fixing commits. Red Hat lists its plan as none available for Red Hat Enterprise Linux 7, 8, 9 and 10 and Red Hat OpenShift Container Platform 4 and 5.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14, 7.3.1, 7.4-rc1

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
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-11-02 Threatist record created from CVE-2026-99218
  2. 2026-11-02 Alias added: GHSA-2cpv-4f6v-pr9h
  3. 2026-11-03 Fix available: Linux/Linux@61d58591aa0188bf2463e263962256316ff8b576, Linux/[email protected] · CNA
  4. 2026-11-03 1 new reference · CNA
  5. 2026-11-04 Priority changed: MEDIUM → LOW
  6. 2026-11-04 Affected versions changed · Red Hat
  7. 2026-11-04 CVSS score added · Red Hat

References

Other 7

  • 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