{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89640 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89640 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-2026-89640 and fix it if it is affected.\n\nWhat it is: CVE-2026-89640 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-2026-89640 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-2026-89640/ (Markdown: https://insights.sbomify.com/CVE-2026-89640/index.md)","id":"CVE-2026-89640","markdown":"https://insights.sbomify.com/CVE-2026-89640/index.md","name":"CVE-2026-89640","record":{"aliases":["AZL-100292","BELL-CVE-2026-89640","DEBIAN-CVE-2026-89640","GHSA-hwfc-7pp7-m5j3","UBUNTU-CVE-2026-89640"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_modify","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel CIFS","requires_auth":"low_privilege","summary":"An integer underflow in the Linux kernel CIFS module allows corrupting file range requests, potentially leading to data corruption or denial of service.","user_interaction":"not_required","vuln_class":"integer_overflow"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.1,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: fix loff_t underflow in cifs_remap_file_range() when len == 0\n\nWith len == 0 (clone to EOF), the effective length is computed as:\n\n    len = src_inode-\u003ei_size - off;\n\nIf off \u003e i_size, this is a negative loff_t, corrupting the ByteCount\nin the FSCTL_DUPLICATE_EXTENTS_TO_FILE request and inverting the range\nin filemap_write_and_wait_range().  The existing off \u003e= i_size check\nfires only after the ioctl has already been sent.\n\nSnapshot i_size_read() once for both the bounds check and the length\ncalculation, eliminating the TOCTOU and 32-bit torn-read risk.  Reject\noff \u003e src_size with -EINVAL.  Treat off == src_size as a no-op,\nconsistent with __generic_remap_file_range_prep().","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":"cifs: fix loff_t underflow in cifs_remap_file_range() when len == 0","id":"CVE-2026-89640","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":"cifs: clear tcon after cifsFileInfo_put() in cifs_file_set_size()","id":"CVE-2026-89641"},"packages":[],"prev":{"headline":"cifs: use cifs_invalidate_cache() in cifs_do_truncate() for O_TRUNC","id":"CVE-2026-89639"},"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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"An integer underflow in the Linux kernel CIFS module allows corrupting file range requests, potentially leading to data corruption or denial of service.","url":"https://insights.sbomify.com/CVE-2026-89640/"}