{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-64514 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-64514 is a denial of service vulnerability in Linux, published on 25 Jul 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-2026-64514 and fix it if it is affected.\n\nWhat it is: CVE-2026-64514 is a denial of service vulnerability in Linux, published on 25 Jul 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-2026-64514 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-2026-64514/ (Markdown: https://insights.sbomify.com/CVE-2026-64514/index.md)","id":"CVE-2026-64514","markdown":"https://insights.sbomify.com/CVE-2026-64514/index.md","name":"CVE-2026-64514","record":{"aliases":["AZL-93608","BELL-CVE-2026-64514","DEBIAN-CVE-2026-64514","GHSA-r2gx-xm5r-33f5","ROOT-OS-UBUNTU-2204-CVE-2026-64514","UBUNTU-CVE-2026-64514"],"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":"low_privilege","summary":"A local attacker can cause a denial of service by triggering a race condition in userfaultfd that leaves threads asleep indefinitely due to incorrect PTE checks.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: gate must_wait writability check on pte_present()\n\nuserfaultfd_must_wait() and userfaultfd_huge_must_wait() read the PTE\nwithout taking the page table lock and then apply pte_write() /\nhuge_pte_write() to it.  Those accessors decode bits from the present\nencoding only; on a swap or migration entry they read the offset bits that\nhappen to share the same position and return an undefined result.\n\nThe intent of the check is \"is this fault still WP-blocked?\".  A\nnon-marker swap entry means the page is in transit -- the userfault\ncontext the original fault delivered against is no longer the same, and\nthe swap-in or migration completion path will re-deliver a fresh fault if\nuserspace still needs to handle it.  Worst case under the current code the\ngarbage write bit says \"wait\", and the thread stays asleep until a\nUFFDIO_WAKE that may never arrive.\n\nGate the writability check on pte_present() so the lockless re-check only\ninspects present-PTE bits when the entry is actually present.  The\nnon-present, non-marker case returns \"don't wait\" and lets the fault path\nretry.","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":"userfaultfd: gate must_wait writability check on pte_present()","id":"CVE-2026-64514","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"wifi: mac80211: fix MLE defragmentation","id":"CVE-2026-64515"},"packages":[],"prev":{"headline":"KVM: x86: Unconditionally recompute CR8 intercept on PPR update","id":"CVE-2026-64513"},"products":["Linux"],"published":"2026-07-25","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-17","vendors":["Linux"]},"summary":"A local attacker can cause a denial of service by triggering a race condition in userfaultfd that leaves threads asleep indefinitely due to incorrect PTE checks.","url":"https://insights.sbomify.com/CVE-2026-64514/"}