{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47044 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47044 is a high-severity vulnerability in Linux kernel, published on 28 Feb 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-2021-47044 and fix it if it is affected.\n\nWhat it is: CVE-2021-47044 is a high-severity vulnerability in Linux kernel, published on 28 Feb 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-2021-47044 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-2021-47044/ (Markdown: https://insights.sbomify.com/CVE-2021-47044/index.md)","id":"CVE-2021-47044","markdown":"https://insights.sbomify.com/CVE-2021-47044/index.md","name":"CVE-2021-47044","record":{"aliases":["DEBIAN-CVE-2021-47044","GHSA-8g29-7ww6-62wf","UBUNTU-CVE-2021-47044"],"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":"none","summary":"An integer overflow in the Linux kernel scheduler can lead to undefined behavior and potential denial of service.","user_interaction":"not_required","vuln_class":"integer_overflow"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.7,"severity":"high","source":"cisa-adp","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-125","name":"Out-of-bounds Read"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/fair: Fix shift-out-of-bounds in load_balance()\n\nSyzbot reported a handful of occurrences where an sd-\u003enr_balance_failed can\ngrow to much higher values than one would expect.\n\nA successful load_balance() resets it to 0; a failed one increments\nit. Once it gets to sd-\u003ecache_nice_tries + 3, this *should* trigger an\nactive balance, which will either set it to sd-\u003ecache_nice_tries+1 or reset\nit to 0. However, in case the to-be-active-balanced task is not allowed to\nrun on env-\u003edst_cpu, then the increment is done without any further\nmodification.\n\nThis could then be repeated ad nauseam, and would explain the absurdly high\nvalues reported by syzbot (86, 149). VincentG noted there is value in\nletting sd-\u003ecache_nice_tries grow, so the shift itself should be\nfixed. That means preventing:\n\n  \"\"\"\n  If the value of the right operand is negative or is greater than or equal\n  to the width of the promoted left operand, the behavior is undefined.\n  \"\"\"\n\nThus we need to cap the shift exponent to\n  BITS_PER_TYPE(typeof(lefthand)) - 1.\n\nI had a look around for other similar cases via coccinelle:\n\n  @expr@\n  position pos;\n  expression E1;\n  expression E2;\n  @@\n  (\n  E1 \u003e\u003e E2@pos\n  |\n  E1 \u003e\u003e E2@pos\n  )\n\n  @cst depends on expr@\n  position pos;\n  expression expr.E1;\n  constant cst;\n  @@\n  (\n  E1 \u003e\u003e cst@pos\n  |\n  E1 \u003c\u003c cst@pos\n  )\n\n  @script:python depends on !cst@\n  pos \u003c\u003c expr.pos;\n  exp \u003c\u003c expr.E2;\n  @@\n  # Dirty hack to ignore constexpr\n  if exp.upper() != exp:\n     coccilib.report.print_report(pos[0], \"Possible UB shift here\")\n\nThe only other match in kernel/sched is rq_clock_thermal() which employs\nsched_thermal_decay_shift, and that exponent is already capped to 10, so\nthat one is fine.","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":"sched/fair: Fix shift-out-of-bounds in load_balance()","id":"CVE-2021-47044","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"integer_overflow","year":"2021"},"n_packages":0,"n_references":4,"next":{"headline":"scsi: lpfc: Fix null pointer dereference in lpfc_prep_els_iocb()","id":"CVE-2021-47045"},"packages":[],"prev":{"headline":"media: venus: core: Fix some resource leaks in the error path of 'venus_probe()'","id":"CVE-2021-47043"},"products":["Linux"],"published":"2024-02-28","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":"An integer overflow in the Linux kernel scheduler can lead to undefined behavior and potential denial of service.","url":"https://insights.sbomify.com/CVE-2021-47044/"}