{ "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" } } } }