What is CVE-2021-47173?

In the Linux kernel, the following vulnerability has been resolved: misc/uss720: fix memory leak in uss720_probe uss720_probe forgets to decrease the refcount of usbdev in uss720_probe. Fix this by decreasing the refcount of usbdev by usb_put_dev. BUG: memory leak unreferenced object 0xffff888101113800 (size 2048): comm "kworker/0:1", pid 7, jiffies 4294956777 (age 28.870s) hex dump (first 32 bytes): ff ff ff ff 31 00 00 00 00 00 00 00 00 00 00 00 ....1........... 00 00 00 00 00 00 00 00 00 00 00 00 03 00 00 00 ................ backtrace: [ ] kmalloc include/linux/slab.h:554 [inline] [ ] kzalloc include/linux/slab.h:684 [inline] [ ] usb_alloc_dev+0x32/0x450 drivers/usb/core/usb.c:582 [ ] hub_port_connect drivers/usb/core/hub.c:5129 [inline] [ ] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] [ ] port_event drivers/usb/core/hub.c:5509 [inline] [ ] hub_event+0x1171/0x20c0 drivers/usb/core/hub.c:5591 [ ] process_one_work+0x2c9/0x600 kernel/workqueue.c:2275 [ ] worker_thread+0x59/0x5d0 kernel/workqueue.c:2421 [ ] kthread+0x178/0x1b0 kernel/kthread.c:292 [ ] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

How severe is CVE-2021-47173?

CVE-2021-47173 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-2021-47173 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47173?

CVE-2021-47173 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47173?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2021-47173 have an EU (EUVD) identifier?

Yes. CVE-2021-47173 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33821.

When was CVE-2021-47173 published?

CVE-2021-47173 was published on 2024-03-25 and last updated on 2026-06-17.

CVE-2021-47173

CVE-2021-47173 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-401.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33821
Weakness: CWE-401
Affected product: Linux Linux Kernel
Published: 2024-03-25
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: misc/uss720: fix memory leak in uss720_probe uss720_probe forgets to decrease the refcount of usbdev in uss720_probe. Fix this by decreasing the refcount of usbdev by usb_put_dev. BUG: memory leak unreferenced object 0xffff888101113800 (size 2048): comm "kworker/0:1", pid 7, jiffies 4294956777 (age 28.870s) hex dump (first 32 bytes): ff ff ff ff 31 00 00 00 00 00 00 00 00 00 00 00 ....1........... 00 00 00 00 00 00 00 00 00 00 00 00 03 00 00 00 ................ backtrace: [<ffffffff82b8e822>] kmalloc include/linux/slab.h:554 [inline] [<ffffffff82b8e822>] kzalloc include/linux/slab.h:684 [inline] [<ffffffff82b8e822>] usb_alloc_dev+0x32/0x450 drivers/usb/core/usb.c:582 [<ffffffff82b98441>] hub_port_connect drivers/usb/core/hub.c:5129 [inline] [<ffffffff82b98441>] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] [<ffffffff82b98441>] port_event drivers/usb/core/hub.c:5509 [inline] [<ffffffff82b98441>] hub_event+0x1171/0x20c0 drivers/usb/core/hub.c:5591 [<ffffffff81259229>] process_one_work+0x2c9/0x600 kernel/workqueue.c:2275 [<ffffffff81259b19>] worker_thread+0x59/0x5d0 kernel/workqueue.c:2421 [<ffffffff81261228>] kthread+0x178/0x1b0 kernel/kthread.c:292 [<ffffffff8100227f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Frequently asked questions

What is CVE-2021-47173?: In the Linux kernel, the following vulnerability has been resolved: misc/uss720: fix memory leak in uss720_probe uss720_probe forgets to decrease the refcount of usbdev in uss720_probe. Fix this by decreasing the refcount of usbdev by usb_put_dev. BUG: memory leak unreferenced object 0xffff888101113800 (size 2048): comm "kworker/0:1", pid 7, jiffies 4294956777 (age 28.870s) hex dump (first 32 bytes): ff ff ff ff 31 00 00 00 00 00 00 00 00 00 00 00 ....1........... 00 00 00 00 00 00 00 00 00 00 00 00 03 00 00 00 ................ backtrace: [<ffffffff82b8e822>] kmalloc include/linux/slab.h:554 [inline] [<ffffffff82b8e822>] kzalloc include/linux/slab.h:684 [inline] [<ffffffff82b8e822>] usb_alloc_dev+0x32/0x450 drivers/usb/core/usb.c:582 [<ffffffff82b98441>] hub_port_connect drivers/usb/core/hub.c:5129 [inline] [<ffffffff82b98441>] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] [<ffffffff82b98441>] port_event drivers/usb/core/hub.c:5509 [inline] [<ffffffff82b98441>] hub_event+0x1171/0x20c0 drivers/usb/core/hub.c:5591 [<ffffffff81259229>] process_one_work+0x2c9/0x600 kernel/workqueue.c:2275 [<ffffffff81259b19>] worker_thread+0x59/0x5d0 kernel/workqueue.c:2421 [<ffffffff81261228>] kthread+0x178/0x1b0 kernel/kthread.c:292 [<ffffffff8100227f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
How severe is CVE-2021-47173?: CVE-2021-47173 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-2021-47173 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47173?: CVE-2021-47173 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47173?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47173 have an EU (EUVD) identifier?: Yes. CVE-2021-47173 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33821.
When was CVE-2021-47173 published?: CVE-2021-47173 was published on 2024-03-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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