# CVE-2021-47173: misc/uss720: fix memory leak in uss720_probe > A memory leak in the uss720 driver allows attackers to exhaust kernel memory, potentially causing a denial of service. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 25 Mar 2024 - **Updated:** 11 May 2026 - **Also known as:** DEBIAN-CVE-2021-47173, GHSA-8rjr-8h65-297v, UBUNTU-CVE-2021-47173 ## What is CVE-2021-47173? CVE-2021-47173 is a medium-severity memory corruption vulnerability in Linux kernel, published on 25 Mar 2024. It can only be exploited from the same machine or local network, with no action from the victim. ### Official 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: [] 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 Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime) ## Which versions are affected by CVE-2021-47173? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2021-47173? Apply the vendor's patch. ## Is CVE-2021-47173 being exploited? There is no known exploitation of CVE-2021-47173 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2021-47173 and fix it if it is affected. What it is: CVE-2021-47173 is a medium-severity memory corruption vulnerability in Linux kernel, published on 25 Mar 2024. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2021-47173 in the wild and no public exploit code. Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2021-47173/ (Markdown: https://insights.sbomify.com/CVE-2021-47173/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47173 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47173 - OSV: https://osv.dev/vulnerability/CVE-2021-47173 --- From sbomify Insights: https://insights.sbomify.com/CVE-2021-47173/ Summaries are generated and may contain mistakes; the official description above is the record.