{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40134 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40134 is a vulnerability in Linux, published on 12 Nov 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-2025-40134 and fix it if it is affected.\n\nWhat it is: CVE-2025-40134 is a vulnerability in Linux, published on 12 Nov 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-2025-40134 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-2025-40134/ (Markdown: https://insights.sbomify.com/CVE-2025-40134/index.md)","id":"CVE-2025-40134","markdown":"https://insights.sbomify.com/CVE-2025-40134/index.md","name":"CVE-2025-40134","record":{"aliases":["BELL-CVE-2025-40134","DEBIAN-CVE-2025-40134","GHSA-m29g-8vpf-pc8m","ROOT-OS-DEBIAN-11-CVE-2025-40134","ROOT-OS-DEBIAN-13-CVE-2025-40134","ROOT-OS-UBUNTU-2404-CVE-2025-40134","UBUNTU-CVE-2025-40134"],"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 race condition in the Linux kernel device-mapper subsystem allows a local attacker to cause a denial of service via a NULL pointer dereference.","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\ndm: fix NULL pointer dereference in __dm_suspend()\n\nThere is a race condition between dm device suspend and table load that\ncan lead to null pointer dereference. The issue occurs when suspend is\ninvoked before table load completes:\n\nBUG: kernel NULL pointer dereference, address: 0000000000000054\nOops: 0000 [#1] PREEMPT SMP PTI\nCPU: 6 PID: 6798 Comm: dmsetup Not tainted 6.6.0-g7e52f5f0ca9b #62\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014\nRIP: 0010:blk_mq_wait_quiesce_done+0x0/0x50\nCall Trace:\n  \u003cTASK\u003e\n  blk_mq_quiesce_queue+0x2c/0x50\n  dm_stop_queue+0xd/0x20\n  __dm_suspend+0x130/0x330\n  dm_suspend+0x11a/0x180\n  dev_suspend+0x27e/0x560\n  ctl_ioctl+0x4cf/0x850\n  dm_ctl_ioctl+0xd/0x20\n  vfs_ioctl+0x1d/0x50\n  __se_sys_ioctl+0x9b/0xc0\n  __x64_sys_ioctl+0x19/0x30\n  x64_sys_call+0x2c4a/0x4620\n  do_syscall_64+0x9e/0x1b0\n\nThe issue can be triggered as below:\n\nT1 \t\t\t\t\t\tT2\ndm_suspend\t\t\t\t\ttable_load\n__dm_suspend\t\t\t\t\tdm_setup_md_queue\n\t\t\t\t\t\tdm_mq_init_request_queue\n\t\t\t\t\t\tblk_mq_init_allocated_queue\n\t\t\t\t\t\t=\u003e q-\u003emq_ops = set-\u003eops; (1)\ndm_stop_queue / dm_wait_for_completion\n=\u003e q-\u003etag_set NULL pointer!\t(2)\n\t\t\t\t\t\t=\u003e q-\u003etag_set = set; (3)\n\nFix this by checking if a valid table (map) exists before performing\nrequest-based suspend and waiting for target I/O. When map is NULL,\nskip these table-dependent suspend steps.\n\nEven when map is NULL, no I/O can reach any target because there is\nno table loaded; I/O submitted in this state will fail early in the\nDM layer. Skipping the table-dependent suspend logic in this case\nis safe and avoids NULL pointer dereferences.","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":"dm: fix NULL pointer dereference in __dm_suspend()","id":"CVE-2025-40134","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2025"},"n_packages":0,"n_references":8,"next":{"headline":"ipv6: use RCU in ip6_xmit()","id":"CVE-2025-40135"},"packages":[],"prev":{"headline":"mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable().","id":"CVE-2025-40133"},"products":["Linux"],"published":"2025-11-12","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 race condition in the Linux kernel device-mapper subsystem allows a local attacker to cause a denial of service via a NULL pointer dereference.","url":"https://insights.sbomify.com/CVE-2025-40134/"}