{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74605", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.919Z", "datePublished": "2026-08-22T15:31:53.063Z", "dateUpdated": "2026-10-15T10:09:20.401Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-15T10:09:20.401Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\neventfs: Use children field for rcu head and add memory barriers\n\nWhen an eventfs inode is freed, it sets ei->is_freed and then uses its\nei->list to add it to the srcu link list as the list field is a union with\nthe rcu list head. As the ei->list is used to iterate over an SRCU\nprotected list without taking the eventfs_mutex, there's nothing stopping\nthe iteration over that list to see the ei->rcu instead of the ei->list\nand it will read a corrupt target.\n\nTo fix this, change the union of the rcu list head with the children list.\nOn freeing the eventfs inode, set the is_free and execute a smp_wmb()\nbefore adding the eventfs inode to the SRCU list.\n\nOn iteration of the ei->children list, at the start, execute a smp_rmb()\nand then read the is_freed of the ei to see if the children list is still\nvalid. If is_freed is set, then the ei_child read is not valid and the\nloop should exit immediately." } ], "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 bug is reached only via local syscalls (getdents64/readdir on tracefs eventfs directories through eventfs_iterate); tracefs is a kernel pseudo-filesystem under /sys/kernel/tracing with no network, adjacent-wireless, or physical-device entry path.\nAC:L - A single multithreaded attacker can loop getdents on events/ or events/kprobes/ while concurrently adding/removing kprobes via kprobe_events writes that call eventfs_remove_dir; the attacker controls both the SRCU list walk and the free path, making the race reliably triggerable.\nPR:L - Exploitation needs only local tracefs read/write access (getdents plus kprobe_events to create/remove eventfs children); kprobe_events checks only LOCKDOWN_TRACEFS and DAC with no capable(), and tracing-group gid mounts, Android/ChromeOS, and developer systems commonly grant this to unprivileged users.\nUI:N - The attacker performs all concurrent directory reads and dynamic event removals in their own process; no separate victim mount, click, or configuration action is required beyond tracefs already being accessible on the system.\nS:U - The union misuse causes kernel heap/list corruption and use-after-free within the tracing filesystem subsystem on the same host; it does not cross VM, container, IOMMU, or other security boundaries to affect a different authority.\nC:H - During list_for_each_entry_srcu over ei->children, a concurrently freed child repurposes ei->list (union with rcu_head) for SRCU teardown, so the iterator follows corrupt list pointers and dereferences freed or attacker-influenced kernel memory typical of UAF read primitives.\nI:H - Corrupt SRCU list traversal over freed eventfs_inode objects is classic kernel UAF memory corruption that can be combined with heap grooming from repeated kprobe create/delete to obtain arbitrary kernel writes and local privilege escalation, not merely a bounded crash.\nA:H - Following a child's list.next after the list/rcu union is switched during free_ei() readily causes invalid pointer dereferences, kernel oops, or panic; the race can be retriggered at will by alternating getdents with dynamic event teardown." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/tracefs/event_inode.c", "fs/tracefs/internal.h" ], "versions": [ { "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e", "lessThan": "2b80707b9e27671e10840d17c6f8f774c4ad9847", "status": "affected", "versionType": "git" }, { "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e", "lessThan": "004f7232e49730448f91665e76bdd7dff8e0c638", "status": "affected", "versionType": "git" }, { "version": "704f960dbee2f1634f4b4e16f208cb16eaf41c1e", "lessThan": "f0ece16ffca7384787b692431961ce202907acf5", "status": "affected", "versionType": "git" }, { "version": "f3f41f444b321ec393edbc251e024fd62658ce55", "status": "affected", "versionType": "git" }, { "version": "305c4e4d80aca2c2d9cf2ebdea56e2eca6d3a6aa", "status": "affected", "versionType": "git" }, { "version": "6.6.18", "lessThan": "6.7", "status": "affected", "versionType": "semver" }, { "version": "6.7.6", "lessThan": "6.8", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/tracefs/event_inode.c", "fs/tracefs/internal.h" ], "versions": [ { "version": "6.8", "status": "affected" }, { "version": "0", "lessThan": "6.8", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.9", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.8", "versionEndExcluding": "6.18.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.1.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7.6" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/2b80707b9e27671e10840d17c6f8f774c4ad9847" }, { "url": "https://git.kernel.org/stable/c/004f7232e49730448f91665e76bdd7dff8e0c638" }, { "url": "https://git.kernel.org/stable/c/f0ece16ffca7384787b692431961ce202907acf5" } ], "title": "eventfs: Use children field for rcu head and add memory barriers", "x_generator": { "engine": "bippy-1.2.0" } } } }