Linux Kernel up to 5.13.3 scsi iscsi_conn_teardown use after free

Summaryinfo

A vulnerability was found in Linux Kernel up to 4.19.197/5.4.133/5.10.51/5.12.18/5.13.3. It has been rated as problematic. Affected by this vulnerability is the function iscsi_conn_teardown of the component scsi. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2021-47328. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 4.19.197/5.4.133/5.10.51/5.12.18/5.13.3. This affects the function iscsi_conn_teardown of the component scsi. 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. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi: Fix conn use after free during resets If we haven't done a unbind target call we can race where iscsi_conn_teardown wakes up the EH thread and then frees the conn while those threads are still accessing the conn ehwait. We can only do one TMF per session so this just moves the TMF fields from the conn to the session. We can then rely on the iscsi_session_teardown->iscsi_remove_session->__iscsi_unbind_session call to remove the target and it's devices, and know after that point there is no device or scsi-ml callout trying to access the session.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47328. 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 12/26/2024).

Upgrading to version 4.19.198, 5.4.134, 5.10.52, 5.12.19 or 5.13.4 eliminates this vulnerability. Applying the patch bf20d85a8838/d04958a348e5/89812e7957ab/f0a031f7c55f/fa9542b35ceb/ec29d0ac29be 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

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.19.197
• 5.4.133
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.10.42
• 5.10.43
• 5.10.44
• 5.10.45
• 5.10.46
• 5.10.47
• 5.10.48
• 5.10.49
• 5.10.50
• 5.10.51
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6
• 5.12.7
• 5.12.8
• 5.12.9
• 5.12.10
• 5.12.11
• 5.12.12
• 5.12.13
• 5.12.14
• 5.12.15
• 5.12.16
• 5.12.17
• 5.12.18
• 5.13.0
• 5.13.1
• 5.13.2
• 5.13.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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