{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47439 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47439 is a medium-severity vulnerability in Linux kernel, published on 22 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-2021-47439 and fix it if it is affected.\n\nWhat it is: CVE-2021-47439 is a medium-severity vulnerability in Linux kernel, published on 22 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-2021-47439 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-2021-47439/ (Markdown: https://insights.sbomify.com/CVE-2021-47439/index.md)","id":"CVE-2021-47439","markdown":"https://insights.sbomify.com/CVE-2021-47439/index.md","name":"CVE-2021-47439","record":{"aliases":["DEBIAN-CVE-2021-47439","GHSA-35q9-qwff-qmh4","UBUNTU-CVE-2021-47439"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A null pointer dereference in the Linux kernel Microchip DSA driver causes a crash when removing the module, leading to denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"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-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: dsa: microchip: Added the condition for scheduling ksz_mib_read_work\n\nWhen the ksz module is installed and removed using rmmod, kernel crashes\nwith null pointer dereferrence error. During rmmod, ksz_switch_remove\nfunction tries to cancel the mib_read_workqueue using\ncancel_delayed_work_sync routine and unregister switch from dsa.\n\nDuring dsa_unregister_switch it calls ksz_mac_link_down, which in turn\nreschedules the workqueue since mib_interval is non-zero.\nDue to which queue executed after mib_interval and it tries to access\ndp-\u003eslave. But the slave is unregistered in the ksz_switch_remove\nfunction. Hence kernel crashes.\n\nTo avoid this crash, before canceling the workqueue, resetted the\nmib_interval to 0.\n\nv1 -\u003e v2:\n-Removed the if condition in ksz_mib_read_work","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":"net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work","id":"CVE-2021-47439","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"net: encx24j600: check error in devm_regmap_init_encx24j600","id":"CVE-2021-47440"},"packages":[],"prev":{"headline":"net/mlx5e: Fix memory leak in mlx5_core_destroy_cq() error path","id":"CVE-2021-47438"},"products":["Linux"],"published":"2024-05-22","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 null pointer dereference in the Linux kernel Microchip DSA driver causes a crash when removing the module, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2021-47439/"}