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TI-2025-15738 Aliases CVE-2025-21786GHSA-jfr9-726h-gv8r

workqueue: Put the pwq after detaching the rescuer from the pool

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 15 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: workqueue: Put the pwq after detaching the rescuer from the pool The commit 68f83057b913("workqueue: Reap workers via kthread_stop() and remove detach_completion") adds code to reap the normal workers but mistakenly does not handle the rescuer and also removes the code waiting for the rescuer in put_unbound_pool(), which caused a use-after-free bug reported by Cheung Wall. To avoid the use-after-free bug, the pool’s reference must be held until the detachment is complete. Therefore, move the code that puts the pwq after detaching the rescuer from the pool.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00232 14th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.12.16, 6.13.4, 6.14Red Hat: 3 advisoriesRed Hat: 15 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.11 and later6.12.16, 6.13.4, 6.14Patch availableCNA
  • Linux VendorLinux Affected 6.11 and later Fixed in 6.12.16, 6.13.4, 6.14 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 6.12.16; 6.13 to before 6.13.4VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 6.12.16; 6.13 to before 6.13.4 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.12.16, 6.13.4, 6.14

Red Hat 3 advisories

  • RHSA-2026:2352 Released 2026-02-09 · Red Hat rating Moderate
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.86.1.el9_6, libperf-5.14.0-570.86.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.86.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.86.1.el9_6, kernel-64k-devel-5.14.0-570.86.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.86.1.el9_6, kernel-64k-5.14.0-570.86.1.el9_6, kernel-64k-core-5.14.0-570.86.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.86.1.el9_6, kernel-rt-64k-5.14.0-570.86.1.el9_6, kernel-rt-64k-core-5.14.0-570.86.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.86.1.el9_6, kernel-rt-core-5.14.0-570.86.1.el9_6, kernel-rt-debug-5.14.0-570.86.1.el9_6 +11
  • RHSA-2025:20518 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.5.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.5.1.el9_7, kernel-64k-devel-5.14.0-611.5.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.5.1.el9_7, kernel-64k-5.14.0-611.5.1.el9_7, kernel-64k-core-5.14.0-611.5.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.5.1.el9_7, libperf-5.14.0-611.5.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-64k-5.14.0-611.5.1.el9_7, kernel-rt-64k-core-5.14.0-611.5.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-core-5.14.0-611.5.1.el9_7, kernel-rt-debug-5.14.0-611.5.1.el9_7 +9
  • RHSA-2025:20095 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.8.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.8.1.el10_1, kernel-64k-devel-6.12.0-124.8.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.8.1.el10_1, kernel-64k-6.12.0-124.8.1.el10_1, kernel-64k-core-6.12.0-124.8.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.8.1.el10_1, libperf-6.12.0-124.8.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-64k-6.12.0-124.8.1.el10_1, kernel-rt-64k-core-6.12.0-124.8.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-core-6.12.0-124.8.1.el10_1, kernel-rt-debug-6.12.0-124.8.1.el10_1 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:2352
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:2352
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:2352
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:2352
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:2352
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-21786
  2. 2026-10-03 Alias added: GHSA-jfr9-726h-gv8r
  3. 2026-10-29 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources