{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47231 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47231 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 May 2024. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-47231 and fix it if it is affected.\n\nWhat it is: CVE-2021-47231 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-47231 in the wild and no public exploit code.\n\nAffected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. 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.\n2. 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.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2021-47231/ (Markdown: https://insights.sbomify.com/CVE-2021-47231/index.md)","id":"CVE-2021-47231","markdown":"https://insights.sbomify.com/CVE-2021-47231/index.md","name":"CVE-2021-47231","record":{"aliases":["DEBIAN-CVE-2021-47231","GHSA-p47x-q59q-2mpw","UBUNTU-CVE-2021-47231"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel CAN driver","requires_auth":"low_privilege","summary":"A memory leak in the Linux kernel's Microchip CAN BUS Analyzer driver allows attackers to exhaust system memory, causing denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"cisa-adp","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-401","name":"Missing Release of Memory after Effective Lifetime"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: mcba_usb: fix memory leak in mcba_usb\n\nSyzbot reported memory leak in SocketCAN driver for Microchip CAN BUS\nAnalyzer Tool. The problem was in unfreed usb_coherent.\n\nIn mcba_usb_start() 20 coherent buffers are allocated and there is\nnothing, that frees them:\n\n1) In callback function the urb is resubmitted and that's all\n2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER\n   is not set (see mcba_usb_start) and this flag cannot be used with\n   coherent buffers.\n\nFail log:\n| [ 1354.053291][ T8413] mcba_usb 1-1:0.0 can0: device disconnected\n| [ 1367.059384][ T8420] kmemleak: 20 new suspected memory leaks (see /sys/kernel/debug/kmem)\n\nSo, all allocated buffers should be freed with usb_free_coherent()\nexplicitly\n\nNOTE:\nThe same pattern for allocating and freeing coherent buffers\nis used in drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"can: mcba_usb: fix memory leak in mcba_usb","id":"CVE-2021-47231","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":6,"next":{"headline":"can: j1939: fix Use-after-Free, hold skb ref while in use","id":"CVE-2021-47232"},"packages":[],"prev":{"headline":"KVM: x86: Immediately reset the MMU context when the SMM flag is cleared","id":"CVE-2021-47230"},"products":["Linux"],"published":"2024-05-21","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A memory leak in the Linux kernel's Microchip CAN BUS Analyzer driver allows attackers to exhaust system memory, causing denial of service.","url":"https://insights.sbomify.com/CVE-2021-47231/"}