{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2024-56673 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2024-56673 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 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-2024-56673 and fix it if it is affected.\n\nWhat it is: CVE-2024-56673 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 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-2024-56673 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-2024-56673/ (Markdown: https://insights.sbomify.com/CVE-2024-56673/index.md)","id":"CVE-2024-56673","markdown":"https://insights.sbomify.com/CVE-2024-56673/index.md","name":"CVE-2024-56673","record":{"aliases":["BELL-CVE-2024-56673","DEBIAN-CVE-2024-56673","GHSA-58c3-gqj2-fvq8","UBUNTU-CVE-2024-56673"],"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 kernel bug in RISC-V memory management causes a crash when tearing down vmemmap page tables, 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":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nriscv: mm: Do not call pmd dtor on vmemmap page table teardown\n\nThe vmemmap's, which is used for RV64 with SPARSEMEM_VMEMMAP, page\ntables are populated using pmd (page middle directory) hugetables.\nHowever, the pmd allocation is not using the generic mechanism used by\nthe VMA code (e.g. pmd_alloc()), or the RISC-V specific\ncreate_pgd_mapping()/alloc_pmd_late(). Instead, the vmemmap page table\ncode allocates a page, and calls vmemmap_set_pmd(). This results in\nthat the pmd ctor is *not* called, nor would it make sense to do so.\n\nNow, when tearing down a vmemmap page table pmd, the cleanup code\nwould unconditionally, and incorrectly call the pmd dtor, which\nresults in a crash (best case).\n\nThis issue was found when running the HMM selftests:\n\n  | tools/testing/selftests/mm# ./test_hmm.sh smoke\n  | ... # when unloading the test_hmm.ko module\n  | page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10915b\n  | flags: 0x1000000000000000(node=0|zone=1)\n  | raw: 1000000000000000 0000000000000000 dead000000000122 0000000000000000\n  | raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000\n  | page dumped because: VM_BUG_ON_PAGE(ptdesc-\u003epmd_huge_pte)\n  | ------------[ cut here ]------------\n  | kernel BUG at include/linux/mm.h:3080!\n  | Kernel BUG [#1]\n  | Modules linked in: test_hmm(-) sch_fq_codel fuse drm drm_panel_orientation_quirks backlight dm_mod\n  | CPU: 1 UID: 0 PID: 514 Comm: modprobe Tainted: G        W          6.12.0-00982-gf2a4f1682d07 #2\n  | Tainted: [W]=WARN\n  | Hardware name: riscv-virtio qemu/qemu, BIOS 2024.10 10/01/2024\n  | epc : remove_pgd_mapping+0xbec/0x1070\n  |  ra : remove_pgd_mapping+0xbec/0x1070\n  | epc : ffffffff80010a68 ra : ffffffff80010a68 sp : ff20000000a73940\n  |  gp : ffffffff827b2d88 tp : ff6000008785da40 t0 : ffffffff80fbce04\n  |  t1 : 0720072007200720 t2 : 706d756420656761 s0 : ff20000000a73a50\n  |  s1 : ff6000008915cff8 a0 : 0000000000000039 a1 : 0000000000000008\n  |  a2 : ff600003fff0de20 a3 : 0000000000000000 a4 : 0000000000000000\n  |  a5 : 0000000000000000 a6 : c0000000ffffefff a7 : ffffffff824469b8\n  |  s2 : ff1c0000022456c0 s3 : ff1ffffffdbfffff s4 : ff6000008915c000\n  |  s5 : ff6000008915c000 s6 : ff6000008915c000 s7 : ff1ffffffdc00000\n  |  s8 : 0000000000000001 s9 : ff1ffffffdc00000 s10: ffffffff819a31f0\n  |  s11: ffffffffffffffff t3 : ffffffff8000c950 t4 : ff60000080244f00\n  |  t5 : ff60000080244000 t6 : ff20000000a73708\n  | status: 0000000200000120 badaddr: ffffffff80010a68 cause: 0000000000000003\n  | [\u003cffffffff80010a68\u003e] remove_pgd_mapping+0xbec/0x1070\n  | [\u003cffffffff80fd238e\u003e] vmemmap_free+0x14/0x1e\n  | [\u003cffffffff8032e698\u003e] section_deactivate+0x220/0x452\n  | [\u003cffffffff8032ef7e\u003e] sparse_remove_section+0x4a/0x58\n  | [\u003cffffffff802f8700\u003e] __remove_pages+0x7e/0xba\n  | [\u003cffffffff803760d8\u003e] memunmap_pages+0x2bc/0x3fe\n  | [\u003cffffffff02a3ca28\u003e] dmirror_device_remove_chunks+0x2ea/0x518 [test_hmm]\n  | [\u003cffffffff02a3e026\u003e] hmm_dmirror_exit+0x3e/0x1018 [test_hmm]\n  | [\u003cffffffff80102c14\u003e] __riscv_sys_delete_module+0x15a/0x2a6\n  | [\u003cffffffff80fd020c\u003e] do_trap_ecall_u+0x1f2/0x266\n  | [\u003cffffffff80fde0a2\u003e] _new_vmalloc_restore_context_a0+0xc6/0xd2\n  | Code: bf51 7597 0184 8593 76a5 854a 4097 0029 80e7 2c00 (9002) 7597\n  | ---[ end trace 0000000000000000 ]---\n  | Kernel panic - not syncing: Fatal exception in interrupt\n\nAdd a check to avoid calling the pmd dtor, if the calling context is\nvmemmap_free().","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":"riscv: mm: Do not call pmd dtor on vmemmap page table teardown","id":"CVE-2024-56673","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2024"},"n_packages":0,"n_references":2,"next":{"headline":"virtio_net: correct netdev_tx_reset_queue() invocation point","id":"CVE-2024-56674"},"packages":[],"prev":{"headline":"blk-cgroup: Fix UAF in blkcg_unpin_online()","id":"CVE-2024-56672"},"products":["Linux"],"published":"2024-12-27","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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A kernel bug in RISC-V memory management causes a crash when tearing down vmemmap page tables, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2024-56673/"}