{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-23181 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-23181 is a vulnerability in Linux, published on 14 Feb 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-2026-23181 and fix it if it is affected.\n\nWhat it is: CVE-2026-23181 is a vulnerability in Linux, published on 14 Feb 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-2026-23181 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-2026-23181/ (Markdown: https://insights.sbomify.com/CVE-2026-23181/index.md)","id":"CVE-2026-23181","markdown":"https://insights.sbomify.com/CVE-2026-23181/index.md","name":"CVE-2026-23181","record":{"aliases":["BELL-CVE-2026-23181","DEBIAN-CVE-2026-23181","GHSA-4fxm-jm89-7f7q","ROOT-OS-UBUNTU-2204-CVE-2026-23181","ROOT-OS-UBUNTU-2404-CVE-2026-23181","UBUNTU-CVE-2026-23181"],"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 btrfs filesystem can cause a null pointer dereference and system crash during mount operations.","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: sync read disk super and set block size\n\nWhen the user performs a btrfs mount, the block device is not set\ncorrectly. The user sets the block size of the block device to 0x4000\nby executing the BLKBSZSET command.\nSince the block size change also changes the mapping-\u003eflags value, this\nfurther affects the result of the mapping_min_folio_order() calculation.\n\nLet's analyze the following two scenarios:\n\nScenario 1: Without executing the BLKBSZSET command, the block size is\n0x1000, and mapping_min_folio_order() returns 0;\n\nScenario 2: After executing the BLKBSZSET command, the block size is\n0x4000, and mapping_min_folio_order() returns 2.\n\ndo_read_cache_folio() allocates a folio before the BLKBSZSET command\nis executed. This results in the allocated folio having an order value\nof 0. Later, after BLKBSZSET is executed, the block size increases to\n0x4000, and the mapping_min_folio_order() calculation result becomes 2.\n\nThis leads to two undesirable consequences:\n\n1. filemap_add_folio() triggers a VM_BUG_ON_FOLIO(folio_order(folio) \u003c\nmapping_min_folio_order(mapping)) assertion.\n\n2. The syzbot report [1] shows a null pointer dereference in\ncreate_empty_buffers() due to a buffer head allocation failure.\n\nSynchronization should be established based on the inode between the\nBLKBSZSET command and read cache page to prevent inconsistencies in\nblock size or mapping flags before and after folio allocation.\n\n[1]\nKASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\nRIP: 0010:create_empty_buffers+0x4d/0x480 fs/buffer.c:1694\nCall Trace:\n folio_create_buffers+0x109/0x150 fs/buffer.c:1802\n block_read_full_folio+0x14c/0x850 fs/buffer.c:2403\n filemap_read_folio+0xc8/0x2a0 mm/filemap.c:2496\n do_read_cache_folio+0x266/0x5c0 mm/filemap.c:4096\n do_read_cache_page mm/filemap.c:4162 [inline]\n read_cache_page_gfp+0x29/0x120 mm/filemap.c:4195\n btrfs_read_disk_super+0x192/0x500 fs/btrfs/volumes.c:1367","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: sync read disk super and set block size","id":"CVE-2026-23181","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"spi: tegra: Fix a memory leak in tegra_slink_probe()","id":"CVE-2026-23182"},"packages":[],"prev":{"headline":"dpaa2-switch: add bounds check for if_id in IRQ handler","id":"CVE-2026-23180"},"products":["Linux"],"published":"2026-02-14","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 btrfs filesystem can cause a null pointer dereference and system crash during mount operations.","url":"https://insights.sbomify.com/CVE-2026-23181/"}