Linux Kernel up to 5.12.2 mhi mhi_queue use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.7$0-$5k0.00

A vulnerability was found in Linux Kernel up to 5.12.2 (Operating System). It has been classified as critical. This affects the function mhi_queue of the component mhi. 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: bus: mhi: core: Fix invalid error returning in mhi_queue mhi_queue returns an error when the doorbell is not accessible in the current state. This can happen when the device is in non M0 state, like M3, and needs to be waken-up prior ringing the DB. This case is managed earlier by triggering an asynchronous M3 exit via controller resume/suspend callbacks, that in turn will cause M0 transition and DB update. So, since it's not an error but just delaying of doorbell update, there is no reason to return an error. This also fixes a use after free error for skb case, indeed a caller queuing skb will try to free the skb if the queueing fails, but in that case queueing has been done.

The weakness was shared 02/27/2024. The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-46969. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/08/2025).

Upgrading to version 5.12.3 or 5.13 eliminates this vulnerability. Applying the patch a99b661c3187/0ecc1c70dcd3 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

Type

Vendor

Name

Version

License

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

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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: 🔍

Local: No
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 5.12.3/5.13
Patch: a99b661c3187/0ecc1c70dcd3

Timelineinfo

02/27/2024 🔍
02/27/2024 +0 days 🔍
02/27/2024 +0 days 🔍
01/08/2025 +316 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-46969 (🔍)
GCVE (CVE): GCVE-0-2021-46969
GCVE (VulDB): GCVE-100-254949

Entryinfo

Created: 02/27/2024 08:08 PM
Updated: 01/08/2025 10:41 PM
Changes: 02/27/2024 08:08 PM (42), 03/14/2024 05:26 PM (1), 01/08/2025 10:41 PM (27)
Complete: 🔍
Cache ID: 18:927:40

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