{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21931 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21931 is a medium-severity vulnerability in Linux kernel, published on 1 Apr 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-2025-21931 and fix it if it is affected.\n\nWhat it is: CVE-2025-21931 is a medium-severity vulnerability in Linux kernel, published on 1 Apr 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-2025-21931 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-2025-21931/ (Markdown: https://insights.sbomify.com/CVE-2025-21931/index.md)","id":"CVE-2025-21931","markdown":"https://insights.sbomify.com/CVE-2025-21931/index.md","name":"CVE-2025-21931","record":{"aliases":["BELL-CVE-2025-21931","DEBIAN-CVE-2025-21931","GHSA-g2g9-6hgr-7f52","ROOT-OS-DEBIAN-11-CVE-2025-21931","ROOT-OS-DEBIAN-12-CVE-2025-21931","ROOT-OS-UBUNTU-2204-CVE-2025-21931","ROOT-OS-UBUNTU-2404-CVE-2025-21931","UBUNTU-CVE-2025-21931"],"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 missing folio lock in the Linux kernel memory hotplug path causes a kernel bug and system crash when offlining hardware-poisoned pages.","user_interaction":"not_required","vuln_class":"race_condition"},"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":[{"id":"CWE-667","name":"Improper Locking"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nhwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio\n\nCommit b15c87263a69 (\"hwpoison, memory_hotplug: allow hwpoisoned pages to\nbe offlined) add page poison checks in do_migrate_range in order to make\noffline hwpoisoned page possible by introducing isolate_lru_page and\ntry_to_unmap for hwpoisoned page.  However folio lock must be held before\ncalling try_to_unmap.  Add it to fix this problem.\n\nWarning will be produced if folio is not locked during unmap:\n\n  ------------[ cut here ]------------\n  kernel BUG at ./include/linux/swapops.h:400!\n  Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP\n  Modules linked in:\n  CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G        W          6.13.0-rc1-00016-g3c434c7ee82a-dirty #41\n  Tainted: [W]=WARN\n  Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015\n  pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n  pc : try_to_unmap_one+0xb08/0xd3c\n  lr : try_to_unmap_one+0x3dc/0xd3c\n  Call trace:\n   try_to_unmap_one+0xb08/0xd3c (P)\n   try_to_unmap_one+0x3dc/0xd3c (L)\n   rmap_walk_anon+0xdc/0x1f8\n   rmap_walk+0x3c/0x58\n   try_to_unmap+0x88/0x90\n   unmap_poisoned_folio+0x30/0xa8\n   do_migrate_range+0x4a0/0x568\n   offline_pages+0x5a4/0x670\n   memory_block_action+0x17c/0x374\n   memory_subsys_offline+0x3c/0x78\n   device_offline+0xa4/0xd0\n   state_store+0x8c/0xf0\n   dev_attr_store+0x18/0x2c\n   sysfs_kf_write+0x44/0x54\n   kernfs_fop_write_iter+0x118/0x1a8\n   vfs_write+0x3a8/0x4bc\n   ksys_write+0x6c/0xf8\n   __arm64_sys_write+0x1c/0x28\n   invoke_syscall+0x44/0x100\n   el0_svc_common.constprop.0+0x40/0xe0\n   do_el0_svc+0x1c/0x28\n   el0_svc+0x30/0xd0\n   el0t_64_sync_handler+0xc8/0xcc\n   el0t_64_sync+0x198/0x19c\n  Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000)\n  ---[ end trace 0000000000000000 ]---","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":"hwpoison, memory_hotplug: lock folio before unmap hwpoisoned folio","id":"CVE-2025-21931","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"race_condition","year":"2025"},"n_packages":0,"n_references":5,"next":{"headline":"mm: abort vma_modify() on merge out of memory failure","id":"CVE-2025-21932"},"packages":[],"prev":{"headline":"wifi: iwlwifi: mvm: don't try to talk to a dead firmware","id":"CVE-2025-21930"},"products":["Linux"],"published":"2025-04-01","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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-23","vendors":["Linux"]},"summary":"A missing folio lock in the Linux kernel memory hotplug path causes a kernel bug and system crash when offlining hardware-poisoned pages.","url":"https://insights.sbomify.com/CVE-2025-21931/"}