{"id":"CVE-2026-31438","title":"netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators\n\nWhen a process crashes and the kernel writes a core dump to a 9P\nfilesystem, __kernel_write() creat…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 18c2e20b42dd21db599e42d05ddaeeb647b2bb6d","Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 4bc2d72c7695cedf6d4e1a558924903c2b28a78e","Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 00d6df7115f6972370974212de9088087820802e","Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 67e467a11f62ff64ad219dc6aa5459e132c79d14","Linux 6.8"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T21:33:22.454848Z"},"published":"2026-04-22","updated":"2026-11-05","sourceUpdated":"2026-11-05T21:33:51.565Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-31438","references":[{"url":"https://git.kernel.org/stable/c/18c2e20b42dd21db599e42d05ddaeeb647b2bb6d"},{"url":"https://git.kernel.org/stable/c/4bc2d72c7695cedf6d4e1a558924903c2b28a78e"},{"url":"https://git.kernel.org/stable/c/00d6df7115f6972370974212de9088087820802e"},{"url":"https://git.kernel.org/stable/c/67e467a11f62ff64ad219dc6aa5459e132c79d14"}],"tags":["cve.org"],"epss":0.00122,"epssPercentile":0.01983,"ingestedAt":"2026-11-05T22:38:32.138Z","slug":"CVE-2026-31438","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators\n\nWhen a process crashes and the kernel writes a core dump to a 9P\nfilesystem, __kernel_write() creates an ITER_KVEC iterator. This\niterator reaches netfs_limit_iter() via netfs_unbuffered_write(), which\nonly handles ITER_FOLIOQ, ITER_BVEC and ITER_XARRAY iterator types,\nhitting the BUG() for any other type.\n\nFix this by adding netfs_limit_kvec() following the same pattern as\nnetfs_limit_bvec(), since both kvec and bvec are simple segment arrays\nwith pointer and length fields. Dispatch it from netfs_limit_iter() when\nthe iterator type is ITER_KVEC.\n\n## Affected\n\n- `Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 18c2e20b42dd21db599e42d05ddaeeb647b2bb6d`\n- `Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 4bc2d72c7695cedf6d4e1a558924903c2b28a78e`\n- `Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 00d6df7115f6972370974212de9088087820802e`\n- `Linux >= cae932d3aee55035a54415dcea8e7ecf2ec469b5 < 67e467a11f62ff64ad219dc6aa5459e132c79d14`\n- `Linux 6.8`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}