{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2025-37964 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-37964 is a high-severity vulnerability in Debian Debian Linux, published on 20 May 2025. 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-2025-37964 and fix it if it is affected.\n\nWhat it is: CVE-2025-37964 is a high-severity vulnerability in Debian Debian Linux, published on 20 May 2025. 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-2025-37964 in the wild and no public exploit code.\n\nAffected product: Debian Debian 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-2025-37964/ (Markdown: https://insights.sbomify.com/CVE-2025-37964/index.md)","id":"CVE-2025-37964","markdown":"https://insights.sbomify.com/CVE-2025-37964/index.md","name":"CVE-2025-37964","record":{"aliases":["BELL-CVE-2025-37964","DEBIAN-CVE-2025-37964","GHSA-xxw2-vx44-7cv6","ROOT-OS-DEBIAN-12-CVE-2025-37964","ROOT-OS-UBUNTU-2204-CVE-2025-37964","UBUNTU-CVE-2025-37964"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_read","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A race condition in Linux kernel TLB flush logic allows stale memory access, potentially leading to information disclosure or privilege escalation.","user_interaction":"not_required","vuln_class":"race_condition"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"linux_kernel","vendor":"linux"}],"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\nx86/mm: Eliminate window where TLB flushes may be inadvertently skipped\n\ntl;dr: There is a window in the mm switching code where the new CR3 is\nset and the CPU should be getting TLB flushes for the new mm.  But\nshould_flush_tlb() has a bug and suppresses the flush.  Fix it by\nwidening the window where should_flush_tlb() sends an IPI.\n\nLong Version:\n\n=== History ===\n\nThere were a few things leading up to this.\n\nFirst, updating mm_cpumask() was observed to be too expensive, so it was\nmade lazier.  But being lazy caused too many unnecessary IPIs to CPUs\ndue to the now-lazy mm_cpumask().  So code was added to cull\nmm_cpumask() periodically[2].  But that culling was a bit too aggressive\nand skipped sending TLB flushes to CPUs that need them.  So here we are\nagain.\n\n=== Problem ===\n\nThe too-aggressive code in should_flush_tlb() strikes in this window:\n\n\t// Turn on IPIs for this CPU/mm combination, but only\n\t// if should_flush_tlb() agrees:\n\tcpumask_set_cpu(cpu, mm_cpumask(next));\n\n\tnext_tlb_gen = atomic64_read(\u0026next-\u003econtext.tlb_gen);\n\tchoose_new_asid(next, next_tlb_gen, \u0026new_asid, \u0026need_flush);\n\tload_new_mm_cr3(need_flush);\n\t// ^ After 'need_flush' is set to false, IPIs *MUST*\n\t// be sent to this CPU and not be ignored.\n\n        this_cpu_write(cpu_tlbstate.loaded_mm, next);\n\t// ^ Not until this point does should_flush_tlb()\n\t// become true!\n\nshould_flush_tlb() will suppress TLB flushes between load_new_mm_cr3()\nand writing to 'loaded_mm', which is a window where they should not be\nsuppressed.  Whoops.\n\n=== Solution ===\n\nThankfully, the fuzzy \"just about to write CR3\" window is already marked\nwith loaded_mm==LOADED_MM_SWITCHING.  Simply checking for that state in\nshould_flush_tlb() is sufficient to ensure that the CPU is targeted with\nan IPI.\n\nThis will cause more TLB flush IPIs.  But the window is relatively small\nand I do not expect this to cause any kind of measurable performance\nimpact.\n\nUpdate the comment where LOADED_MM_SWITCHING is written since it grew\nyet another user.\n\nPeter Z also raised a concern that should_flush_tlb() might not observe\n'loaded_mm' and 'is_lazy' in the same order that switch_mm_irqs_off()\nwrites them.  Add a barrier to ensure that they are observed in the\norder they are written.","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/mm: Eliminate window where TLB flushes may be inadvertently skipped","id":"CVE-2025-37964","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux","linux:linux_kernel"],"type":"race_condition","year":"2025"},"n_packages":0,"n_references":6,"next":{"headline":"drm/amd/display: Fix invalid context error in dml helper","id":"CVE-2025-37965"},"packages":[],"prev":{"headline":"arm64: bpf: Only mitigate cBPF programs loaded by unprivileged users","id":"CVE-2025-37963"},"products":["Linux"],"published":"2025-05-20","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"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":"A race condition in Linux kernel TLB flush logic allows stale memory access, potentially leading to information disclosure or privilege escalation.","url":"https://insights.sbomify.com/CVE-2025-37964/"}