Linux Kernel up to 5.12.12 USB smsc75xx_bind use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.12.12. This vulnerability affects the function smsc75xx_bind of the component USB Handler. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2021-47239. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.12.12. This vulnerability affects the function smsc75xx_bind of the component USB Handler. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: usb: fix possible use-after-free in smsc75xx_bind The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind") fails to clean up the work scheduled in smsc75xx_reset-> smsc75xx_set_multicast, which leads to use-after-free if the work is scheduled to start after the deallocation. In addition, this patch also removes a dangling pointer - dev->data[0]. This patch calls cancel_work_sync to cancel the scheduled work and set the dangling pointer to NULL.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2021-47239 since 04/10/2024. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 12/30/2024).

Upgrading to version 4.4.274, 4.9.274, 4.14.238, 4.19.196, 5.4.128, 5.10.46 or 5.12.13 eliminates this vulnerability. Applying the patch 7cc8b2e05fce/64160d1741a3/c4e3be2e7742/2fc8300c9cfa/4252bf6c2b24/570a52cf3e01/14616c372a7b/56b786d86694 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.4.274/4.9.274/4.14.238/4.19.196/5.4.128/5.10.46/5.12.13
Patch: 7cc8b2e05fce/64160d1741a3/c4e3be2e7742/2fc8300c9cfa/4252bf6c2b24/570a52cf3e01/14616c372a7b/56b786d86694

Timelineinfo

04/10/2024 🔍
05/21/2024 +41 days 🔍
05/21/2024 +0 days 🔍
12/30/2024 +223 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-47239 (🔍)
GCVE (CVE): GCVE-0-2021-47239
GCVE (VulDB): GCVE-100-265708

Entryinfo

Created: 05/21/2024 20:24
Updated: 12/30/2024 20:16
Changes: 05/21/2024 20:24 (57), 12/30/2024 20:16 (13)
Complete: 🔍
Cache ID: 216::103

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