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TI-2025-26540 Aliases CVE-2025-39866GHSA-65ww-5pr7-752v

fs: writeback: fix use-after-free in __mark_inode_dirty()

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: 10 fixed, 3 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: fs: writeback: fix use-after-free in __mark_inode_dirty() An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching. CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198 Root cause is: systemd-random-seed kworker ---------------------------------------------------------------------- ___mark_inode_dirty inode_switch_wbs_work_fn spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00314 24th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.247, 5.15.192, 6.1.151 +4Red Hat: 2 advisoriesRed Hat: 10 fixed, 3 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
LinuxLinux4.2 and later5.10.247, 5.15.192, 6.1.151, 6.6.105, 6.12.46, 6.16.6, 6.17Patch availableCNA
  • Linux VendorLinux Affected 4.2 and later Fixed in 5.10.247, 5.15.192, 6.1.151, 6.6.105, 6.12.46, 6.16.6, 6.17 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*4.2 to before 5.10.247; 5.11 to before 5.15.192; 5.16 to before 6.1.151; 6.2 to before 6.6.105; 6.7 to before 6.12.46; 6.13 to before 6.16.6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*6.17 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*6.17 rc2VulnerableLinux
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.2 to before 5.10.247; 5.11 to before 5.15.192; 5.16 to before 6.1.151; 6.2 to before 6.6.105; 6.7 to before 6.12.46; 6.13 to before 6.16.6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* Versions 6.17 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:* Versions 6.17 rc2 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.247, 5.15.192, 6.1.151, 6.6.105, 6.12.46, 6.16.6, 6.17

Red Hat 2 advisories

  • RHSA-2026:18587 Released 2026-05-19 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.5.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.5.1.el9_8, kernel-64k-devel-5.14.0-687.5.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.5.1.el9_8, kernel-64k-5.14.0-687.5.1.el9_8, kernel-64k-core-5.14.0-687.5.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.5.1.el9_8, libperf-5.14.0-687.5.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.5.1.el9_8, kernel-rt-64k-5.14.0-687.5.1.el9_8, kernel-rt-64k-core-5.14.0-687.5.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.5.1.el9_8, kernel-rt-core-5.14.0-687.5.1.el9_8, kernel-rt-debug-5.14.0-687.5.1.el9_8 +9
  • RHSA-2026:18134 Released 2026-05-19 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.7.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.7.1.el10_2, kernel-64k-devel-6.12.0-211.7.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.7.1.el10_2, kernel-64k-6.12.0-211.7.1.el10_2, kernel-64k-core-6.12.0-211.7.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.7.1.el10_2, libperf-6.12.0-211.7.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.7.1.el10_2, kernel-rt-64k-6.12.0-211.7.1.el10_2, kernel-rt-64k-core-6.12.0-211.7.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.7.1.el10_2, kernel-rt-core-6.12.0-211.7.1.el10_2, kernel-rt-debug-6.12.0-211.7.1.el10_2 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:18587
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:18587
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:18587
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:18587
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:18587
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-39866
  2. 2026-10-03 Alias added: GHSA-65ww-5pr7-752v
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-23 Affected versions changed · Red Hat
  5. 2026-10-23 CVSS score changed · Red Hat

References

Patch 7

Advisory 1

  • 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

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