Linux Kernel up to 6.9.5 greybus gb_interface_release use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.9.5 and classified as critical. This affects the function gb_interface_release of the component greybus. Performing a manipulation results in use after free. This vulnerability was named CVE-2024-39495. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.9.5. This affects the function gb_interface_release of the component greybus. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: greybus: Fix use-after-free bug in gb_interface_release due to race condition. In gb_interface_create, &intf->mode_switch_completion is bound with gb_interface_mode_switch_work. Then it will be started by gb_interface_request_mode_switch. Here is the relevant code. if (!queue_work(system_long_wq, &intf->mode_switch_work)) { ... } If we call gb_interface_release to make cleanup, there may be an unfinished work. This function will call kfree to free the object "intf". However, if gb_interface_mode_switch_work is scheduled to run after kfree, it may cause use-after-free error as gb_interface_mode_switch_work will use the object "intf". The possible execution flow that may lead to the issue is as follows: CPU0 CPU1 | gb_interface_create | gb_interface_request_mode_switch gb_interface_release | kfree(intf) (free) | | gb_interface_mode_switch_work | mutex_lock(&intf->mutex) (use) Fix it by canceling the work before kfree.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2024-39495 since 06/25/2024. The exploitability is told to be difficult. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/26/2024).

The vulnerability scanner Nessus provides a plugin with the ID 207802 (ubuntu_linux USN-7003-4: Ubuntu 20.04 LTS : Linux kernel vulnerabilities (USN-7003-4)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.279, 5.10.221, 5.15.162, 6.1.95, 6.6.35 or 6.9.6 eliminates this vulnerability. Applying the patch 74cd0a421896/2b6bb0b4abfd/fb071f5c75d4/9a733d69a4a5/0b8fba38bdfb/03ea2b129344/5c9c5d7f26ac 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.

The vulnerability is also documented in the vulnerability database at Tenable (207802). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.1
VulDB Temp Score: 6.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector (Linux): 🔍

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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Nessus ID: 207802
Nessus Name: ubuntu_linux USN-7003-4: Ubuntu 20.04 LTS : Linux kernel vulnerabilities (USN-7003-4)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.4.279/5.10.221/5.15.162/6.1.95/6.6.35/6.9.6
Patch: 74cd0a421896/2b6bb0b4abfd/fb071f5c75d4/9a733d69a4a5/0b8fba38bdfb/03ea2b129344/5c9c5d7f26ac

Timelineinfo

06/25/2024 🔍
07/12/2024 +17 days 🔍
07/12/2024 +0 days 🔍
09/26/2024 +76 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2024-39495 (🔍)
GCVE (CVE): GCVE-0-2024-39495
GCVE (VulDB): GCVE-100-271323

Entryinfo

Created: 07/12/2024 17:05
Updated: 09/26/2024 22:54
Changes: 07/12/2024 17:05 (58), 07/25/2024 02:47 (12), 08/20/2024 23:23 (12), 09/26/2024 22:54 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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