{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89579 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89579 is a high-severity vulnerability in Linux, published on 11 Sep 2026. 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-2026-89579 and fix it if it is affected.\n\nWhat it is: CVE-2026-89579 is a high-severity vulnerability in Linux, published on 11 Sep 2026. 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-2026-89579 in the wild and no public exploit code.\n\nAffected product: Linux. 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-2026-89579/ (Markdown: https://insights.sbomify.com/CVE-2026-89579/index.md)","id":"CVE-2026-89579","markdown":"https://insights.sbomify.com/CVE-2026-89579/index.md","name":"CVE-2026-89579","record":{"aliases":["BELL-CVE-2026-89579","DEBIAN-CVE-2026-89579","GHSA-pw4c-42f8-r7j7","UBUNTU-CVE-2026-89579"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","code_execution"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"Integer overflow in Linux kernel BPF bloom filter allows local privilege escalation on 32-bit x86 systems.","user_interaction":"not_required","vuln_class":"integer_overflow"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Harden bloom filter sizing and indexing on 32-bit kernels\n\nbloom_map_alloc() has two 32-bit-specific problems when the computed\nbitmap reaches the U32_MAX fallback case.\n\nFirst, BITS_TO_BYTES(U32_MAX) is evaluated with 32-bit arithmetic. The\naddition performed by DIV_ROUND_UP wraps, so the map allocates only the\nfixed-size bloom filter object while keeping bitset_mask == U32_MAX.\nSubsequent updates can then write past the allocated object.\n\nSecond, fixing only the allocation size is not sufficient. The bloom hash\nis a u32, but set_bit() takes a signed long bit number and x86 test_bit()\neventually feeds the index to variable_test_bit(long, ...). On 32-bit\nkernels, hashes in [0x80000000, U32_MAX] therefore become negative bit\noffsets. x86 bt/bts with a memory operand interpret those offsets relative\nto the supplied base, so a map with bitset_mask == U32_MAX can read or\nwrite before bloom-\u003ebitset even after allocating the full 512 MiB bitmap.\n\nKeep the U32_MAX fallback, but split each hash into a word pointer and an\nin-word bit number before calling test_bit() or set_bit(). The bitops\nargument is then always in [0, BITS_PER_LONG - 1], while BIT_WORD(h) still\nselects the intended word in the full bitmap.\n\nCompute the bitset size from (u64)bitset_mask + 1 before passing the final\nsize to bpf_map_area_alloc(). This fixes the original under-allocation and\nkeeps the allocated storage consistent with the addressable bitset.\n\nExploitation note: local privilege escalation is possible on a 32-bit x86\nkernel using the under-allocation bug from a binary with CAP_BPF.","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: Harden bloom filter sizing and indexing on 32-bit kernels","id":"CVE-2026-89579","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"integer_overflow","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"bpf: Disable preemption in __bpf_get_stack","id":"CVE-2026-89580"},"packages":[],"prev":{"headline":"dm-io: clone the source bio instead of copying its biovec","id":"CVE-2026-89578"},"products":["Linux"],"published":"2026-09-11","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"Integer overflow in Linux kernel BPF bloom filter allows local privilege escalation on 32-bit x86 systems.","url":"https://insights.sbomify.com/CVE-2026-89579/"}