CVE-2023-53641

Medium

In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: hif_usb: fix memory leak of remain_skbs hif_dev->remain_skb is allocated and used exclusively in ath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is processed and subsequently freed (in error paths) only during the next call of ath9k_hif_usb_rx_stream(). So, if the urbs are deallocated between those two calls due to the device deinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream() is not called next time and the allocated remain_skb is leaked. Our local Syzkaller instance was able to trigger that. remain_skb makes sense when receiving two consecutive urbs which are logically linked together, i.e. a specific data field from the first skb indicates a cached skb to be allocated, memcpy'd with some data and subsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs deallocation supposedly makes that link irrelevant so we need to free the cached skb in those cases. Fix the leak by introducing a function to explicitly free remain_skb (if it is not NULL) when the rx urbs have been deallocated. remain_skb is NULL when it has not been allocated at all (hif_dev struct is kzalloced) or when it has been processed in next call to ath9k_hif_usb_rx_stream(). Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Package Linux Kernel
Published 2025-10-07
Last modified 2026-02-03
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-401

CVE-2023-53641 is a Memory Leak vulnerability

What is Memory Leak?

The product does not release memory after use, causing gradual resource exhaustion. Learn more on MITRE CWE

Affected versions

Linux kernel versions 2.6.35 and later are affected. Fixed in 4.19.283, 5.4.243, 5.10.180, 5.15.111, 6.1.28, 6.2.15, 6.3.2, 6.4 and their respective stable series.

Affected from
≥ 2.6.35
Fixed in
✓ 4.19.283 4.19.x ✓ 5.4.243 5.4.x ✓ 5.10.180 5.10.x ✓ 5.15.111 5.15.x ✓ 6.1.28 6.1.x ✓ 6.2.15 6.2.x ✓ 6.3.2 6.3.x ✓ 6.4

References

The following references provide additional information about CVE-2023-53641 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2023-53641?

    CVE-2023-53641 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a Memory Leak flaw (CWE-401) . It affects Linux kernel versions from 2.6.35 onward and has been patched in 4.19.283, 5.4.243, 5.10.180 and others. CVE-2023-53641 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2023-53641?

    CVE-2023-53641 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2023-53641?

    Yes — CVE-2023-53641 has been patched. Fixed versions include 4.19.283, 5.4.243, 5.10.180 and others. If you are running Linux kernel 2.6.35 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2023-53641 actively exploited?

    No — CVE-2023-53641 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Memory Leak (CWE-401)?

    The product does not release memory after use, causing gradual resource exhaustion. View CWE-401 on MITRE CWE →