{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47463 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47463 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-2021-47463 and fix it if it is affected.\n\nWhat it is: CVE-2021-47463 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-2021-47463 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-2021-47463/ (Markdown: https://insights.sbomify.com/CVE-2021-47463/index.md)","id":"CVE-2021-47463","markdown":"https://insights.sbomify.com/CVE-2021-47463/index.md","name":"CVE-2021-47463","record":{"aliases":["DEBIAN-CVE-2021-47463","GHSA-xjr2-g37g-hrjm","UBUNTU-CVE-2021-47463"],"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's secretmem module allows local attackers to cause a system crash via KVM operations.","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\nmm/secretmem: fix NULL page-\u003emapping dereference in page_is_secretmem()\n\nCheck for a NULL page-\u003emapping before dereferencing the mapping in\npage_is_secretmem(), as the page's mapping can be nullified while gup()\nis running, e.g.  by reclaim or truncation.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000068\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] PREEMPT SMP NOPTI\n  CPU: 6 PID: 4173897 Comm: CPU 3/KVM Tainted: G        W\n  RIP: 0010:internal_get_user_pages_fast+0x621/0x9d0\n  Code: \u003c48\u003e 81 7a 68 80 08 04 bc 0f 85 21 ff ff 8 89 c7 be\n  RSP: 0018:ffffaa90087679b0 EFLAGS: 00010046\n  RAX: ffffe3f37905b900 RBX: 00007f2dd561e000 RCX: ffffe3f37905b934\n  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffe3f37905b900\n  ...\n  CR2: 0000000000000068 CR3: 00000004c5898003 CR4: 00000000001726e0\n  Call Trace:\n   get_user_pages_fast_only+0x13/0x20\n   hva_to_pfn+0xa9/0x3e0\n   try_async_pf+0xa1/0x270\n   direct_page_fault+0x113/0xad0\n   kvm_mmu_page_fault+0x69/0x680\n   vmx_handle_exit+0xe1/0x5d0\n   kvm_arch_vcpu_ioctl_run+0xd81/0x1c70\n   kvm_vcpu_ioctl+0x267/0x670\n   __x64_sys_ioctl+0x83/0xa0\n   do_syscall_64+0x56/0x80\n   entry_SYSCALL_64_after_hwframe+0x44/0xae","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":"mm/secretmem: fix NULL page-\u003emapping dereference in page_is_secretmem()","id":"CVE-2021-47463","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":2,"next":{"headline":"audit: fix possible null-pointer dereference in audit_filter_rules","id":"CVE-2021-47464"},"packages":[],"prev":{"headline":"mm/mempolicy: do not allow illegal MPOL_F_NUMA_BALANCING | MPOL_LOCAL in mbind()","id":"CVE-2021-47462"},"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's secretmem module allows local attackers to cause a system crash via KVM operations.","url":"https://insights.sbomify.com/CVE-2021-47463/"}