CVE-2021-47049: Drivers: hv: vmbus: Use after free in __vmbus_open()

Published Feb 28, 2024
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

Drivers: hv: vmbus: Use after free in vmbusopen()

The "openinfo" variable is added to the &vmbusconnection.chnmsglist, but the error handling frees "openinfo" without removing it from the list. This will result in a use after free. First remove it from the list, and then free it.

Affected Software

3 affected components
Linux Linux kernel>=4.14<5.10.37
Linux Linux kernel>=5.11<5.11.21
Linux Linux kernel>=5.12<5.12.4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Configuration

    In the Linux kernel vmbus code, ensure the error-handling path does not free open_info without first removing it from the list (&vmbus_connection.chn_msg_list). The fix described is to add open_info to &vmbus_connection.chn_msg_list and ensure cleanup removes it from the list before free to prevent use-after-free.

    Linux kernel (vmbus: __vmbus_open) Fix resolved by adding open_info handling to vmbus_connection.chn_msg_list and correcting error handling = Resolved as described (add open_info to &vmbus_connection.chn_msg_list; ensure error handling removes it before freeing)

Event History

Feb 28, 2024
CVE Published
via MITRE·08:13 AM
Data Sourced
via MITRE·08:13 AM
DescriptionSeverity
Data Sourced
via NVD·09:15 AM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-47049?

CVE-2021-47049 has been classified as a high-severity vulnerability due to its potential impact on system stability and security.

2

How do I fix CVE-2021-47049?

To fix CVE-2021-47049, update your Linux kernel to a version that exceeds 5.12.4, 5.11.21, or 5.10.37.

3

What is the impact of CVE-2021-47049?

The impact of CVE-2021-47049 includes potential exploitation leading to system crashes and possible remote code execution.

4

Which versions of the Linux kernel are affected by CVE-2021-47049?

CVE-2021-47049 affects Linux kernel versions between 4.14 and 5.10.37, as well as versions from 5.11 to 5.11.21, and 5.12 up to 5.12.4.

5

What components are involved in CVE-2021-47049?

CVE-2021-47049 involves the drivers for Hyper-V, particularly affecting the vmbus component during the vmbus_open() process.

Contact

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