{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40235 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40235 is a vulnerability in Linux, published on 4 Dec 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-2025-40235 and fix it if it is affected.\n\nWhat it is: CVE-2025-40235 is a vulnerability in Linux, published on 4 Dec 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-2025-40235 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-2025-40235/ (Markdown: https://insights.sbomify.com/CVE-2025-40235/index.md)","id":"CVE-2025-40235","markdown":"https://insights.sbomify.com/CVE-2025-40235/index.md","name":"CVE-2025-40235","record":{"aliases":["BELL-CVE-2025-40235","DEBIAN-CVE-2025-40235","GHSA-x64m-4w9m-w2j3","ROOT-OS-UBUNTU-2404-CVE-2025-40235","UBUNTU-CVE-2025-40235"],"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 trigger a kernel crash by mounting a btrfs filesystem with specific allocation failures, causing a denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"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\nbtrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots()\n\nIf fs_info-\u003esuper_copy or fs_info-\u003esuper_for_commit allocated failed in\nbtrfs_get_tree_subvol(), then no need to call btrfs_free_fs_info().\nOtherwise btrfs_check_leaked_roots() would access NULL pointer because\nfs_info-\u003eallocated_roots had not been initialised.\n\nsyzkaller reported the following information:\n  ------------[ cut here ]------------\n  BUG: unable to handle page fault for address: fffffffffffffbb0\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 64c9067 P4D 64c9067 PUD 64cb067 PMD 0\n  Oops: Oops: 0000 [#1] SMP KASAN PTI\n  CPU: 0 UID: 0 PID: 1402 Comm: syz.1.35 Not tainted 6.15.8 #4 PREEMPT(lazy)\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), (...)\n  RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]\n  RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]\n  RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]\n  RIP: 0010:refcount_read include/linux/refcount.h:170 [inline]\n  RIP: 0010:btrfs_check_leaked_roots+0x18f/0x2c0 fs/btrfs/disk-io.c:1230\n  [...]\n  Call Trace:\n   \u003cTASK\u003e\n   btrfs_free_fs_info+0x310/0x410 fs/btrfs/disk-io.c:1280\n   btrfs_get_tree_subvol+0x592/0x6b0 fs/btrfs/super.c:2029\n   btrfs_get_tree+0x63/0x80 fs/btrfs/super.c:2097\n   vfs_get_tree+0x98/0x320 fs/super.c:1759\n   do_new_mount+0x357/0x660 fs/namespace.c:3899\n   path_mount+0x716/0x19c0 fs/namespace.c:4226\n   do_mount fs/namespace.c:4239 [inline]\n   __do_sys_mount fs/namespace.c:4450 [inline]\n   __se_sys_mount fs/namespace.c:4427 [inline]\n   __x64_sys_mount+0x28c/0x310 fs/namespace.c:4427\n   do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n   do_syscall_64+0x92/0x180 arch/x86/entry/syscall_64.c:94\n   entry_SYSCALL_64_after_hwframe+0x76/0x7e\n  RIP: 0033:0x7f032eaffa8d\n  [...]","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":"btrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots()","id":"CVE-2025-40235","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2025"},"n_packages":0,"n_references":3,"next":{"headline":"virtio-net: zero unused hash fields","id":"CVE-2025-40236"},"packages":[],"prev":{"headline":"platform/x86: alienware-wmi-wmax: Fix NULL pointer dereference in sleep handlers","id":"CVE-2025-40234"},"products":["Linux"],"published":"2025-12-04","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":"2026-05-11","vendors":["Linux"]},"summary":"A local attacker can trigger a kernel crash by mounting a btrfs filesystem with specific allocation failures, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2025-40235/"}