{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47376 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47376 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-2021-47376 and fix it if it is affected.\n\nWhat it is: CVE-2021-47376 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-2021-47376 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-2021-47376/ (Markdown: https://insights.sbomify.com/CVE-2021-47376/index.md)","id":"CVE-2021-47376","markdown":"https://insights.sbomify.com/CVE-2021-47376/index.md","name":"CVE-2021-47376","record":{"aliases":["DEBIAN-CVE-2021-47376","GHSA-p793-3f2h-38xw","UBUNTU-CVE-2021-47376"],"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 missing size check in the Linux kernel BPF verifier can trigger a kernel warning and potential denial of service when loading oversized BTF information.","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":"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":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Add oversize check before call kvcalloc()\n\nCommit 7661809d493b (\"mm: don't allow oversized kvmalloc() calls\") add the\noversize check. When the allocation is larger than what kmalloc() supports,\nthe following warning triggered:\n\nWARNING: CPU: 0 PID: 8408 at mm/util.c:597 kvmalloc_node+0x108/0x110 mm/util.c:597\nModules linked in:\nCPU: 0 PID: 8408 Comm: syz-executor221 Not tainted 5.14.0-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nRIP: 0010:kvmalloc_node+0x108/0x110 mm/util.c:597\nCall Trace:\n kvmalloc include/linux/mm.h:806 [inline]\n kvmalloc_array include/linux/mm.h:824 [inline]\n kvcalloc include/linux/mm.h:829 [inline]\n check_btf_line kernel/bpf/verifier.c:9925 [inline]\n check_btf_info kernel/bpf/verifier.c:10049 [inline]\n bpf_check+0xd634/0x150d0 kernel/bpf/verifier.c:13759\n bpf_prog_load kernel/bpf/syscall.c:2301 [inline]\n __sys_bpf+0x11181/0x126e0 kernel/bpf/syscall.c:4587\n __do_sys_bpf kernel/bpf/syscall.c:4691 [inline]\n __se_sys_bpf kernel/bpf/syscall.c:4689 [inline]\n __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4689\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\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":"bpf: Add oversize check before call kvcalloc()","id":"CVE-2021-47376","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":4,"next":{"headline":"This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.","id":"CVE-2021-47377"},"packages":[],"prev":{"headline":"blktrace: Fix uaf in blk_trace access after removing by sysfs","id":"CVE-2021-47375"},"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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A missing size check in the Linux kernel BPF verifier can trigger a kernel warning and potential denial of service when loading oversized BTF information.","url":"https://insights.sbomify.com/CVE-2021-47376/"}