CVE-2021-47170

CVE-2021-47170 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: USB: usbfs: Don't WARN about excessively large memory allocations Syzbot found that the kernel generates a WARNing if the user tries to submit a bulk transfer through usbfs with a buffer that is way too large. This isn't a bug in the kernel; it's merely an invalid request from the user and the usbfs code does handle it correctly. In theory the same thing can happen with async transfers, or with the packet descriptor table for isochronous transfers. To prevent the MM subsystem from complaining about these bad allocation requests, add the __GFP_NOWARN flag to the kmalloc calls for these buffers.

Frequently asked questions

What is CVE-2021-47170?
In the Linux kernel, the following vulnerability has been resolved: USB: usbfs: Don't WARN about excessively large memory allocations Syzbot found that the kernel generates a WARNing if the user tries to submit a bulk transfer through usbfs with a buffer that is way too large. This isn't a bug in the kernel; it's merely an invalid request from the user and the usbfs code does handle it correctly. In theory the same thing can happen with async transfers, or with the packet descriptor table for isochronous transfers. To prevent the MM subsystem from complaining about these bad allocation requests, add the __GFP_NOWARN flag to the kmalloc calls for these buffers.
How severe is CVE-2021-47170?
CVE-2021-47170 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47170 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47170?
CVE-2021-47170 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47170?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47170 have an EU (EUVD) identifier?
Yes. CVE-2021-47170 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33818.
When was CVE-2021-47170 published?
CVE-2021-47170 was published on 2024-03-25 and last updated on 2026-06-17.

References

Affected products (4)

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