Cloudanix VulnDB

CVE-2023-53529

None

CVSS

—

EPSS

0.1%

Published

Oct 1, 2025

CISA due date

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Cloudanix analysis

Schedule a fix SSVC: Track

A bug in how Linux handles certain USB WiFi adapters wastes memory each time the device is plugged in, which can eventually slow down or crash the computer if left unfixed.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Low
Impact
Denial Of Service
Component
OS kernel
Class
Memory Corruption
Remediation
Patch
Effort
Low
Patch risk
Low

What it actually does

Memory leak in the rtw88_usb driver probe routine allocates kernel memory via kmalloc_trace that is never freed, leaving dangling allocations until module unload.

Why it matters to the business

Repeated insertion or probing of affected USB WiFi devices gradually consumes kernel memory, risking system instability, performance degradation, or crashes on long-running Linux systems.

How an attack unfolds

An attacker with physical or local access repeatedly inserts or triggers USB device enumeration on vulnerable systems to force repeated allocations in rtw_usb_probe without corresponding frees, exhausting memory over time.

How to fix it

Upgrade the Linux kernel to a fixed version such as 5.10.70-1 (Debian 11), 5.14.6-1 (Debian 12/13/14), or commit 5bba1ad561a8b5bb14704d8f511cf10466336e3d in stable trees; unload and reload the driver after update if feasible.

How to confirm the fix worked

Run kmemleak after loading/unloading the rtw_usb module to confirm no unreferenced objects remain; verify kernel version matches or exceeds the listed fixed releases via uname -r.

Typical attack path

  1. Obtain physical or local access to a system with the vulnerable rtw_usb module loaded
  2. Insert or enumerate affected USB WiFi devices to invoke rtw_usb_probe
  3. Repeat device insertion/removal cycles to accumulate unreferenced allocations
  4. Monitor for memory pressure or kernel oops resulting from exhaustion

How to detect it

Review kernel logs for kmemleak reports referencing rtw_usb_probe allocations; inspect dmesg or /sys/kernel/debug/kmemleak for unreferenced objects with backtraces pointing to rtw_usb; correlate USB device insertion events with rising slab memory usage.

What your security team should do

  • Prioritize kernel package updates on all systems using rtw88_usb WiFi hardware
  • Monitor memory usage and kmemleak reports on affected hosts
  • Restrict physical USB access where possible until patches are applied
  • Test driver reload behavior post-upgrade to ensure deinit frees allocations

The record

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw88: Fix memory leak in rtw88_usb Kmemleak shows the following leak arising from routine in the usb probe routine: unreferenced object 0xffff895cb29bba00 (size 512): comm "(udev-worker)", pid 534, jiffies 4294903932 (age 102751.088s) hex dump (first 32 bytes): 77 30 30 30 00 00 00 00 02 2f 2d 2b 30 00 00 00 w000...../-+0... 02 00 2a 28 00 00 00 00 ff 55 ff ff ff 00 00 00 ..*(.....U...... backtrace: [<ffffffff9265fa36>] kmalloc_trace+0x26/0x90 [<ffffffffc17eec41>] rtw_usb_probe+0x2f1/0x680 [rtw_usb] [<ffffffffc03e19fd>] usb_probe_interface+0xdd/0x2e0 [usbcore] [<ffffffff92b4f2fe>] really_probe+0x18e/0x3d0 [<ffffffff92b4f5b8>] __driver_probe_device+0x78/0x160 [<ffffffff92b4f6bf>] driver_probe_device+0x1f/0x90 [<ffffffff92b4f8df>] __driver_attach+0xbf/0x1b0 [<ffffffff92b4d350>] bus_for_each_dev+0x70/0xc0 [<ffffffff92b4e51e>] bus_add_driver+0x10e/0x210 [<ffffffff92b50935>] driver_register+0x55/0xf0 [<ffffffffc03e0708>] usb_register_driver+0x88/0x140 [usbcore] [<ffffffff92401153>] do_one_initcall+0x43/0x210 [<ffffffff9254f42a>] do_init_module+0x4a/0x200 [<ffffffff92551d1c>] __do_sys_finit_module+0xac/0x120 [<ffffffff92ee6626>] do_syscall_64+0x56/0x80 [<ffffffff9300006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 The leak was verified to be real by unloading the driver, which resulted in a dangling pointer to the allocation. The allocated memory is freed in rtw_usb_intf_deinit().

Affected packages

Ecosystem Package Introduced Fixed
Linux Kernel 5.2.0 6.3.4

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