{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64217","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T15:36:31.770Z","datePublished":"2026-07-24T15:23:05.261Z","dateUpdated":"2026-08-05T12:40:05.203Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:40:05.203Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix overrun check in netfs_extract_user_iter()\n\nFix netfs_extract_user_iter() so that if iov_iter_extract_pages() overfills\npages[], then those pages don't get included in the iterator constructed at\nthe end of the function.  If there was an overfill, memory corruption has\nalready happened."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable helper is reached through local direct or unbuffered I/O against CIFS/SMB3, AFS, or 9P files. Remote peers cannot directly control the local user iterator that triggers extraction.\nAC:L - The attacker controls and can repeatedly submit the UBUF or IOVEC layout, and corruption occurs synchronously once the overfill condition is reached. No race, timing window, or victim-controlled state is required.\nPR:L - An ordinary unprivileged process with permission to access a file on an existing affected mount can reach the helper. No capability or administrative privilege is checked on the I/O path.\nUI:N - The attacker directly opens and performs I/O on the accessible file without requiring another user to act. An existing affected mount is a deployment prerequisite, not per-attack victim interaction.\nS:U - The corruption compromises the same host kernel that processes the local I/O. It does not inherently cross a VM, IOMMU, or other distinct security authority.\nC:H - The overfill writes page pointers beyond the allocated kernel buffer and the malformed bvec can subsequently access unpopulated descriptors. Exploitation of this kernel heap corruption can expose arbitrary kernel memory.\nI:H - The bug produces an out-of-bounds kernel heap write and can cause adjacent memory to be interpreted as bvec descriptors. Heap grooming could turn this into arbitrary memory modification or control-flow hijacking.\nA:H - The corruption can cause a kernel oops, panic, or hang, while aborted extraction can also leak pinned pages. An attacker can repeat the triggering I/O to sustain denial of service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/netfs/iterator.c"],"versions":[{"version":"85dd2c8ff368b1446be9febde84afe1d7aec4261","lessThan":"00efe58bbdcc93272d579ca24bfc912563f4a204","status":"affected","versionType":"git"},{"version":"85dd2c8ff368b1446be9febde84afe1d7aec4261","lessThan":"96cc3beb2390ba9f9c128c5733c0ccfe450dd4f9","status":"affected","versionType":"git"},{"version":"85dd2c8ff368b1446be9febde84afe1d7aec4261","lessThan":"afeb32d9bf9aaeea51d0f723a19f14afb73bd94d","status":"affected","versionType":"git"},{"version":"85dd2c8ff368b1446be9febde84afe1d7aec4261","lessThan":"f48b9157f0f611fa436c360648603d5ded719b12","status":"affected","versionType":"git"},{"version":"85dd2c8ff368b1446be9febde84afe1d7aec4261","lessThan":"0ef37eef83fad3542ee06db2940433ae1a92b39d","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/netfs/iterator.c"],"versions":[{"version":"6.3","status":"affected"},{"version":"0","lessThan":"6.3","status":"unaffected","versionType":"semver"},{"version":"6.6.142","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.92","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.34","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.11","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.6.142"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.12.92"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"6.18.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"7.0.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/00efe58bbdcc93272d579ca24bfc912563f4a204"},{"url":"https://git.kernel.org/stable/c/96cc3beb2390ba9f9c128c5733c0ccfe450dd4f9"},{"url":"https://git.kernel.org/stable/c/afeb32d9bf9aaeea51d0f723a19f14afb73bd94d"},{"url":"https://git.kernel.org/stable/c/f48b9157f0f611fa436c360648603d5ded719b12"},{"url":"https://git.kernel.org/stable/c/0ef37eef83fad3542ee06db2940433ae1a92b39d"}],"title":"netfs: Fix overrun check in netfs_extract_user_iter()","x_generator":{"engine":"bippy-1.2.0"}}}}