Linux Kernel up to 5.17.1 ufx_usb_probe null pointer dereference

Summaryinfo

A vulnerability labeled as problematic has been found in Linux Kernel up to 5.17.1. This issue affects the function ufx_usb_probe. Such manipulation leads to null pointer dereference. This vulnerability is documented as CVE-2021-47652. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.17.1 and classified as problematic. Affected by this issue is the function ufx_usb_probe. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: video: fbdev: smscufx: Fix null-ptr-deref in ufx_usb_probe() I got a null-ptr-deref report: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... RIP: 0010:fb_destroy_modelist+0x38/0x100 ... Call Trace: ufx_usb_probe.cold+0x2b5/0xac1 [smscufx] usb_probe_interface+0x1aa/0x3c0 [usbcore] really_probe+0x167/0x460 ... ret_from_fork+0x1f/0x30 If fb_alloc_cmap() fails in ufx_usb_probe(), fb_destroy_modelist() will be called to destroy modelist in the error handling path. But modelist has not been initialized yet, so it will result in null-ptr-deref. Initialize modelist before calling fb_alloc_cmap() to fix this bug.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2021-47652 since 02/26/2025. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

Upgrading to version 4.9.311, 4.14.276, 4.19.238, 5.4.189, 5.10.110, 5.15.33, 5.16.19 or 5.17.2 eliminates this vulnerability. Applying the patch d1b6a1f0c23b7164250479bf92e2893291dca539/0fd28daec73525382e5c992db8743bf76e42cd5c/dd3a6cc7385b89ec2303f39dfc3bafa4e24cec4b/da8b269cc0a2526ebeaccbe2484c999eb0f822cf/64ec3e678d76419f207b9cdd338dda438ca10b1c/c420b540db4b5d69de0a36d8b9d9a6a79a04f05a/d396c651e2b508b6179bb678cc029f3becbf5170/9280ef235b05e8f19f8bc6d547b992f0a0ef398d/1791f487f877a9e83d81c8677bd3e7b259e7cb27 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

• 4.9.310
• 4.14.275
• 4.19.237
• 5.4.188
• 5.10.109
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10
• 5.16.11
• 5.16.12
• 5.16.13
• 5.16.14
• 5.16.15
• 5.16.16
• 5.16.17
• 5.16.18
• 5.17.0
• 5.17.1

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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