CyberSecBulletin
CVE-2025-38731NVD status: Modified

Linux: Double Free

CVE-2025-38731 is a high-severity double free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 77a946bf1af0e8110ef6e243394217a17f9b7e33, 111fb43a557726079a67ce3ab51f602ddbf7097e as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 77a946bf1af0e8110ef6e243394217a17f9b7e33 or 111fb43a557726079a67ce3ab51f602ddbf7097e, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.16.4 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxb43e864af0d4e74636c0e1dee857ce3275a84829 up to, but not including, 77a946bf1af0e8110ef6e243394217a17f9b7e33; b43e864af0d4e74636c0e1dee857ce3275a84829 up to, but not including, 111fb43a557726079a67ce3ab51f602ddbf7097e; 6.1577a946bf1af0e8110ef6e243394217a17f9b7e33, 111fb43a557726079a67ce3ab51f602ddbf7097e
LinuxLinux Kernel6.15 up to, but not including, 6.16.4; 6.176.16.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix vm_bind_ioctl double free bug If the argument check during an array bind fails, the bind_ops are freed twice as seen below. Fix this by setting bind_ops to NULL after freeing. ================================================================== BUG: KASAN: double-free in xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] Free of addr ffff88813bb9b800 by task xe_vm/14198 CPU: 5 UID: 0 PID: 14198 Comm: xe_vm Not tainted 6.16.0-xe-eudebug-cmanszew+ #520 PREEMPT(full) Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR5 RVP, BIOS ADLPFWI1.R00.2411.A02.2110081023 10/08/2021 Call Trace: <TASK> dump_stack_lvl+0x82/0xd0 print_report+0xcb/0x610 ? __virt_addr_valid+0x19a/0x300 ? xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] kasan_report_invalid_free+0xc8/0xf0 ? xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] ? xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] check_slab_allocation+0x102/0x130 kfree+0x10d/0x440 ? should_fail_ex+0x57/0x2f0 ? xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] xe_vm_bind_ioctl+0x1b2/0x21f0 [xe] ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe] ? __lock_acquire+0xab9/0x27f0 ? lock_acquire+0x165/0x300 ? drm_dev_enter+0x53/0xe0 [drm] ? find_held_lock+0x2b/0x80 ? drm_dev_exit+0x30/0x50 [drm] ? drm_ioctl_kernel+0x128/0x1c0 [drm] drm_ioctl_kernel+0x128/0x1c0 [drm] ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe] ? find_held_lock+0x2b/0x80 ? __pfx_drm_ioctl_kernel+0x10/0x10 [drm] ? should_fail_ex+0x57/0x2f0 ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe] drm_ioctl+0x352/0x620 [drm] ? __pfx_drm_ioctl+0x10/0x10 [drm] ? __pfx_rpm_resume+0x10/0x10 ? do_raw_spin_lock+0x11a/0x1b0 ? find_held_lock+0x2b/0x80 ? __pm_runtime_resume+0x61/0xc0 ? rcu_is_watching+0x20/0x50 ? trace_irq_enable.constprop.0+0xac/0xe0 xe_drm_ioctl+0x91/0xc0 [xe] __x64_sys_ioctl+0xb2/0x100 ? rcu_is_watching+0x20/0x50 do_syscall_64+0x68/0x2e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fa9acb24ded (cherry picked from commit a01b704527c28a2fd43a17a85f8996b75ec8492a)

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Double Free

The product calls free() twice on the same memory address.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
  • Use a static analysis tool to find double free instances.

More Double Free vulnerabilities (CWE-415)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Double Free vulnerabilities

Spotted an error? Tell us.