{"id":"CVE-2026-64160","state":"PUBLISHED","title":"netfs: Fix potential for tearing in ->remote_i_size and ->zero_point","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix potential for tearing in ->remote_i_size and ->zero_point\n\nFix potential tearing in using ->remote_i_size and ->zero_point by copying\ni_size_read() and i_size_write() and using the same seqcount as for i_size.\n\nWe need to make sure that netfslib and the filesystems that use it always\nhold i_lock whilst updating any of the sizes to prevent i_size_seqcount\nfrom getting corrupted.","publishedAt":"2026-07-19T15:40:47.063Z","updatedAt":"2026-10-19T20:28:14.119Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4058f742105ecfcbdf99e1139e6c1f74fb8e6db9","status":"affected","lessThan":"55970f238d495517edc961d55c44c772594d0969","versionType":"git"},{"version":"4058f742105ecfcbdf99e1139e6c1f74fb8e6db9","status":"affected","lessThan":"2c8f4742bb76117d735f92a3932d85239b16c494","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/9p/v9fs_vfs.h","fs/9p/vfs_inode.c","fs/9p/vfs_inode_dotl.c","fs/afs/file.c","fs/afs/inode.c","fs/afs/internal.h","fs/afs/write.c","fs/netfs/buffered_read.c","fs/netfs/buffered_write.c","fs/netfs/direct_write.c","fs/netfs/misc.c","fs/netfs/write_collect.c","fs/smb/client/cifsfs.c","fs/smb/client/cifssmb.c","fs/smb/client/file.c","fs/smb/client/inode.c","fs/smb/client/readdir.c","fs/smb/client/smb2ops.c","fs/smb/client/smb2pdu.c","include/linux/netfs.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.18","versionType":"semver"},{"version":"7.0.11","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/9p/v9fs_vfs.h","fs/9p/vfs_inode.c","fs/9p/vfs_inode_dotl.c","fs/afs/file.c","fs/afs/inode.c","fs/afs/internal.h","fs/afs/write.c","fs/netfs/buffered_read.c","fs/netfs/buffered_write.c","fs/netfs/direct_write.c","fs/netfs/misc.c","fs/netfs/write_collect.c","fs/smb/client/cifsfs.c","fs/smb/client/cifssmb.c","fs/smb/client/file.c","fs/smb/client/inode.c","fs/smb/client/readdir.c","fs/smb/client/smb2ops.c","fs/smb/client/smb2pdu.c","include/linux/netfs.h"]}],"references":["https://git.kernel.org/stable/c/55970f238d495517edc961d55c44c772594d0969","https://git.kernel.org/stable/c/2c8f4742bb76117d735f92a3932d85239b16c494"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64160.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64160","state":"PUBLISHED","datePublished":"2026-07-19T15:40:47.063Z","dateUpdated":"2026-10-19T20:28:14.119Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.038Z"},"containers":{"cna":{"title":"netfs: Fix potential for tearing in ->remote_i_size and ->zero_point","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix potential for tearing in ->remote_i_size and ->zero_point\n\nFix potential tearing in using ->remote_i_size and ->zero_point by copying\ni_size_read() and i_size_write() and using the same seqcount as for i_size.\n\nWe need to make sure that netfslib and the filesystems that use it always\nhold i_lock whilst updating any of the sizes to prevent i_size_seqcount\nfrom getting corrupted."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4058f742105ecfcbdf99e1139e6c1f74fb8e6db9","status":"affected","lessThan":"55970f238d495517edc961d55c44c772594d0969","versionType":"git"},{"version":"4058f742105ecfcbdf99e1139e6c1f74fb8e6db9","status":"affected","lessThan":"2c8f4742bb76117d735f92a3932d85239b16c494","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/9p/v9fs_vfs.h","fs/9p/vfs_inode.c","fs/9p/vfs_inode_dotl.c","fs/afs/file.c","fs/afs/inode.c","fs/afs/internal.h","fs/afs/write.c","fs/netfs/buffered_read.c","fs/netfs/buffered_write.c","fs/netfs/direct_write.c","fs/netfs/misc.c","fs/netfs/write_collect.c","fs/smb/client/cifsfs.c","fs/smb/client/cifssmb.c","fs/smb/client/file.c","fs/smb/client/inode.c","fs/smb/client/readdir.c","fs/smb/client/smb2ops.c","fs/smb/client/smb2pdu.c","include/linux/netfs.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.18","versionType":"semver"},{"version":"7.0.11","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/9p/v9fs_vfs.h","fs/9p/vfs_inode.c","fs/9p/vfs_inode_dotl.c","fs/afs/file.c","fs/afs/inode.c","fs/afs/internal.h","fs/afs/write.c","fs/netfs/buffered_read.c","fs/netfs/buffered_write.c","fs/netfs/direct_write.c","fs/netfs/misc.c","fs/netfs/write_collect.c","fs/smb/client/cifsfs.c","fs/smb/client/cifssmb.c","fs/smb/client/file.c","fs/smb/client/inode.c","fs/smb/client/readdir.c","fs/smb/client/smb2ops.c","fs/smb/client/smb2pdu.c","include/linux/netfs.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/55970f238d495517edc961d55c44c772594d0969"},{"url":"https://git.kernel.org/stable/c/2c8f4742bb76117d735f92a3932d85239b16c494"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The bug is in netfs client code (CIFS/SMB, AFS, 9p) reached when processing network filesystem protocol responses and concurrent I/O; a malicious remote server can drive attribute/size updates that race with client read/write paths.\nAC:L - The attacker controls both sides of the race by timing SMB/AFS/9p responses against concurrent local read/write/DIO operations, or by spawning parallel threads performing file I/O on the same inode.\nPR:N - A remote malicious filesystem server needs no privileges on the victim host; exploitation only requires the victim system to perform routine I/O against a mounted attacker-controlled or MITM'd network share.\nUI:N - No per-attack discretionary user action is required beyond an existing CIFS/AFS/9p mount and normal automated or concurrent file access, which is typical in enterprise and embedded deployments.\nS:U - Impact is confined to the victim kernel's netfs client subsystem and does not cross a VM, IOMMU, or other security-authority boundary.\nC:H - Torn 64-bit size values produce attacker-influenceable arbitrary bounds used in read-length and EOF decisions, potentially causing out-of-bounds kernel reads or stale-cache data exposure beyond intended file ranges.\nI:H - Corrupted size metadata causes incorrect zero-filling, skipped server reads, and wrong EOF handling, enabling arbitrary modification of file content visible to applications and incorrect size metadata written back to the server.\nA:H - Unsynchronized writes can corrupt i_size_seqcount, causing i_size_read() and related readers to spin forever, producing soft lockups and denial of service for affected inodes and dependent processes."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:39:50.187Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"7.0.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-64160","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:37:03.470970Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-362","lang":"en","type":"CWE","description":"CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:28:14.119Z"}}]}}}