{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47217 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47217 is a medium-severity vulnerability in Linux kernel, published on 10 Apr 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-2021-47217 and fix it if it is affected.\n\nWhat it is: CVE-2021-47217 is a medium-severity vulnerability in Linux kernel, published on 10 Apr 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-2021-47217 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-2021-47217/ (Markdown: https://insights.sbomify.com/CVE-2021-47217/index.md)","id":"CVE-2021-47217","markdown":"https://insights.sbomify.com/CVE-2021-47217/index.md","name":"CVE-2021-47217","record":{"aliases":["DEBIAN-CVE-2021-47217","GHSA-9jpw-f586-mqqf","UBUNTU-CVE-2021-47217"],"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 Hyper-V driver causes a system crash if Hyper-V setup fails, 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":"nvd","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\nx86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails\n\nCheck for a valid hv_vp_index array prior to derefencing hv_vp_index when\nsetting Hyper-V's TSC change callback.  If Hyper-V setup failed in\nhyperv_init(), the kernel will still report that it's running under\nHyper-V, but will have silently disabled nearly all functionality.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000010\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP\n  CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:set_hv_tscchange_cb+0x15/0xa0\n  Code: \u003c8b\u003e 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08\n  ...\n  Call Trace:\n   kvm_arch_init+0x17c/0x280\n   kvm_init+0x31/0x330\n   vmx_init+0xba/0x13a\n   do_one_initcall+0x41/0x1c0\n   kernel_init_freeable+0x1f2/0x23b\n   kernel_init+0x16/0x120\n   ret_from_fork+0x22/0x30","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":"x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails","id":"CVE-2021-47217","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":5,"next":{"headline":"selinux: fix NULL-pointer dereference when hashtab allocation fails","id":"CVE-2021-47218"},"packages":[],"prev":{"headline":"scsi: advansys: Fix kernel pointer leak","id":"CVE-2021-47216"},"products":["Linux"],"published":"2024-04-10","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 Hyper-V driver causes a system crash if Hyper-V setup fails, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2021-47217/"}