{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-43073 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-43073 is a medium-severity vulnerability in Linux kernel, published on 5 May 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-2026-43073 and fix it if it is affected.\n\nWhat it is: CVE-2026-43073 is a medium-severity vulnerability in Linux kernel, published on 5 May 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-2026-43073 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-2026-43073/ (Markdown: https://insights.sbomify.com/CVE-2026-43073/index.md)","id":"CVE-2026-43073","markdown":"https://insights.sbomify.com/CVE-2026-43073/index.md","name":"CVE-2026-43073","record":{"aliases":["BELL-CVE-2026-43073","DEBIAN-CVE-2026-43073","GHSA-w93x-73ch-q28m","ROOT-OS-DEBIAN-11-CVE-2026-43073","ROOT-OS-DEBIAN-12-CVE-2026-43073","ROOT-OS-UBUNTU-2204-CVE-2026-43073","ROOT-OS-UBUNTU-2404-CVE-2026-43073","UBUNTU-CVE-2026-43073"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["other"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"The Linux kernel renamed a misleadingly named memory copy function to improve code clarity and prevent misuse by drivers, with no direct security impact stated.","user_interaction":"not_required","vuln_class":"other"},"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\nx86-64: rename misleadingly named '__copy_user_nocache()' function\n\nThis function was a masterclass in bad naming, for various historical\nreasons.\n\nIt claimed to be a non-cached user copy.  It is literally _neither_ of\nthose things.  It's a specialty memory copy routine that uses\nnon-temporal stores for the destination (but not the source), and that\ndoes exception handling for both source and destination accesses.\n\nAlso note that while it works for unaligned targets, any unaligned parts\n(whether at beginning or end) will not use non-temporal stores, since\nonly words and quadwords can be non-temporal on x86.\n\nThe exception handling means that it _can_ be used for user space\naccesses, but not on its own - it needs all the normal \"start user space\naccess\" logic around it.\n\nBut typically the user space access would be the source, not the\nnon-temporal destination.  That was the original intention of this,\nwhere the destination was some fragile persistent memory target that\nneeded non-temporal stores in order to catch machine check exceptions\nsynchronously and deal with them gracefully.\n\nThus that non-descriptive name: one use case was to copy from user space\ninto a non-cached kernel buffer.  However, the existing users are a mix\nof that intended use-case, and a couple of random drivers that just did\nthis as a performance tweak.\n\nSome of those random drivers then actively misused the user copying\nversion (with STAC/CLAC and all) to do kernel copies without ever even\ncaring about the exception handling, _just_ for the non-temporal\ndestination.\n\nRename it as a first small step to actually make it halfway sane, and\nchange the prototype to be more normal: it doesn't take a user pointer\nunless the caller has done the proper conversion, and the argument size\nis the full size_t (it still won't actually copy more than 4GB in one\ngo, but there's also no reason to silently truncate the size argument in\nthe caller).\n\nFinally, use this now sanely named function in the NTB code, which\nmis-used a user copy version (with STAC/CLAC and all) of this interface\ndespite it not actually being a user copy at all.","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":"x86-64: rename misleadingly named '__copy_user_nocache()' function","id":"CVE-2026-43073","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"other","year":"2026"},"n_packages":0,"n_references":7,"next":{"headline":"eventpoll: defer struct eventpoll free to RCU grace period","id":"CVE-2026-43074"},"packages":[],"prev":{"headline":"drm/vc4: platform_get_irq_byname() returns an int","id":"CVE-2026-43072"},"products":["Linux"],"published":"2026-05-05","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-21","vendors":["Linux"]},"summary":"The Linux kernel renamed a misleadingly named memory copy function to improve code clarity and prevent misuse by drivers, with no direct security impact stated.","url":"https://insights.sbomify.com/CVE-2026-43073/"}