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CVE-2023-52439

HIGHCVSS 7.8/10EPSS 0.30%

Last modified

CVE-2023-52439 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: uio: Fix use-after-free in uio_open core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. EPSS estimates a 0.30% chance of exploitation in the next 30 days.

Description

In the Linux kernel, the following vulnerability has been resolved: uio: Fix use-after-free in uio_open core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock.

Metrics

CVSS 3.1
7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
0.30%

21.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
LinuxLinux Kernel> 4.18.0, < 4.19.306
LinuxLinux Kernel>= 4.20.0, < 5.4.268
LinuxLinux Kernel>= 5.5.0, < 5.10.209
LinuxLinux Kernel>= 5.11.0, < 5.15.148
LinuxLinux Kernel>= 5.16.0, < 6.1.74
LinuxLinux Kernel>= 6.2.0, < 6.6.13
LinuxLinux Kernel>= 6.7.0, < 6.7.1
LinuxLinux Kernel4.18

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2023-52439?
In the Linux kernel, the following vulnerability has been resolved: uio: Fix use-after-free in uio_open core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock.
How severe is CVE-2023-52439?
CVE-2023-52439 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.30% probability of exploitation in the next 30 days.
How do I fix CVE-2023-52439?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-52439?

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Source: NVD / NIST