{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-23100 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-23100 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 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-2026-23100 and fix it if it is affected.\n\nWhat it is: CVE-2026-23100 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 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-2026-23100 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-2026-23100/ (Markdown: https://insights.sbomify.com/CVE-2026-23100/index.md)","id":"CVE-2026-23100","markdown":"https://insights.sbomify.com/CVE-2026-23100/index.md","name":"CVE-2026-23100","record":{"aliases":["AZL-80285","BELL-CVE-2026-23100","DEBIAN-CVE-2026-23100","GHSA-4rhr-9xj2-x9gx","ROOT-OS-DEBIAN-11-CVE-2026-23100","ROOT-OS-DEBIAN-12-CVE-2026-23100","ROOT-OS-DEBIAN-13-CVE-2026-23100","ROOT-OS-UBUNTU-2204-CVE-2026-23100","ROOT-OS-UBUNTU-2404-CVE-2026-23100","UBUNTU-CVE-2026-23100"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_read","other"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"Incorrect shared PMD detection in Linux kernel hugetlb allows non-exclusive folio migration and incorrect memory accounting, potentially leading to data integrity issues.","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\nmm/hugetlb: fix hugetlb_pmd_shared()\n\nPatch series \"mm/hugetlb: fixes for PMD table sharing (incl.  using\nmmu_gather)\", v3.\n\nOne functional fix, one performance regression fix, and two related\ncomment fixes.\n\nI cleaned up my prototype I recently shared [1] for the performance fix,\ndeferring most of the cleanups I had in the prototype to a later point. \nWhile doing that I identified the other things.\n\nThe goal of this patch set is to be backported to stable trees \"fairly\"\neasily. At least patch #1 and #4.\n\nPatch #1 fixes hugetlb_pmd_shared() not detecting any sharing\nPatch #2 + #3 are simple comment fixes that patch #4 interacts with.\nPatch #4 is a fix for the reported performance regression due to excessive\nIPI broadcasts during fork()+exit().\n\nThe last patch is all about TLB flushes, IPIs and mmu_gather.\nRead: complicated\n\nThere are plenty of cleanups in the future to be had + one reasonable\noptimization on x86. But that's all out of scope for this series.\n\nRuntime tested, with a focus on fixing the performance regression using\nthe original reproducer [2] on x86.\n\nThis patch (of 4):\n\nWe switched from (wrongly) using the page count to an independent shared\ncount.  Now, shared page tables have a refcount of 1 (excluding\nspeculative references) and instead use ptdesc-\u003ept_share_count to identify\nsharing.\n\nWe didn't convert hugetlb_pmd_shared(), so right now, we would never\ndetect a shared PMD table as such, because sharing/unsharing no longer\ntouches the refcount of a PMD table.\n\nPage migration, like mbind() or migrate_pages() would allow for migrating\nfolios mapped into such shared PMD tables, even though the folios are not\nexclusive.  In smaps we would account them as \"private\" although they are\n\"shared\", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the\npagemap interface.\n\nFix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared().","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":"mm/hugetlb: fix hugetlb_pmd_shared()","id":"CVE-2026-23100","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":"leds: led-class: Only Add LED to leds_list when it is fully ready","id":"CVE-2026-23101"},"packages":[],"prev":{"headline":"bonding: limit BOND_MODE_8023AD to Ethernet devices","id":"CVE-2026-23099"},"products":["Linux"],"published":"2026-02-04","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":"2026-10-15","vendors":["Linux"]},"summary":"Incorrect shared PMD detection in Linux kernel hugetlb allows non-exclusive folio migration and incorrect memory accounting, potentially leading to data integrity issues.","url":"https://insights.sbomify.com/CVE-2026-23100/"}