CVE-2021-47652
MediumIn 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.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-476CVE-2021-47652 is a NULL Pointer Dereference vulnerability
What is NULL Pointer Dereference?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE
Affected versions
Linux kernel versions
3.2
and later are affected. Fixed in
4.9.311,
4.14.276,
4.19.238,
5.4.189,
5.10.110,
5.15.33,
5.16.19,
5.17.2,
5.18
and their respective stable series.
References
The following references provide additional information about CVE-2021-47652 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/0fd28daec73525382e5c992db8743bf76e42cd5c
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PatchKernel patch commithttps://git.kernel.org/stable/c/1791f487f877a9e83d81c8677bd3e7b259e7cb27
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PatchKernel patch commithttps://git.kernel.org/stable/c/64ec3e678d76419f207b9cdd338dda438ca10b1c
Frequently asked questions
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What is CVE-2021-47652?
CVE-2021-47652 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 3.2 onward and has been patched in 4.9.311, 4.14.276, 4.19.238 and others. CVE-2021-47652 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2021-47652?
CVE-2021-47652 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2021-47652?
Yes — CVE-2021-47652 has been patched. Fixed versions include 4.9.311, 4.14.276, 4.19.238 and others. If you are running Linux kernel 3.2 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2021-47652 actively exploited?
No — CVE-2021-47652 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is NULL Pointer Dereference (CWE-476)?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →