{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43074", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.982Z", "datePublished": "2026-05-06T07:21:58.210Z", "dateUpdated": "2026-08-05T12:25:45.708Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:25:45.708Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\neventpoll: defer struct eventpoll free to RCU grace period\n\nIn certain situations, ep_free() in eventpoll.c will kfree the epi->ep\neventpoll struct while it still being used by another concurrent thread.\nDefer the kfree() to an RCU callback to prevent UAF." } ], "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 path is reached through local epoll syscalls, primarily `epoll_ctl(EPOLL_CTL_ADD)` on nested epoll descriptors racing with descriptor close/release. Network input is not sufficient to reach the lifetime bug without local control of epoll file descriptors.\nAC:L - The race is attacker-controlled: an unprivileged local process can create the epoll graph and run concurrent threads performing nested `epoll_ctl()` and close/release operations. No rare external state or victim timing is required beyond winning a race the attacker can repeatedly drive.\nPR:L - Creating epoll descriptors and calling `epoll_ctl()` require only ordinary local user privileges. No capability check gates the vulnerable nested epoll path; the only capability-related logic masks `EPOLLWAKEUP` and is not relevant.\nUI:N - Exploitation does not require another user to open files, mount anything, or perform any action. The attacking process can create, nest, and close all relevant descriptors itself.\nS:U - The impact is within the kernel security authority as a local kernel memory corruption or privilege escalation. There is no VM escape, IOMMU bypass, or cross-authority boundary change shown by this bug.\nC:H - This is a use-after-free of `struct eventpoll` during an RCU walk, and the stale pointer can be dereferenced after the object is freed and potentially reallocated. Per kernel CVSS guidance, a UAF is treated as enabling high confidentiality impact through exploitable memory corruption.\nI:H - The stale `struct eventpoll` is not only read but also written via fields such as `gen` and `loop_check_depth` after free, making heap corruption plausible if the memory is reallocated. Per kernel CVSS guidance, UAF memory corruption supports high integrity impact.\nA:H - At minimum, dereferencing or writing a freed `struct eventpoll` can crash or corrupt the kernel. A local attacker can repeatedly trigger the race, so availability impact is high." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/eventpoll.c" ], "versions": [ { "version": "f2451def095c1743adcfcb0cb5dadc86034e162a", "lessThan": "902120be4f44947df6311002addc7faf69bdbff1", "status": "affected", "versionType": "git" }, { "version": "a1f93804449d13f97dabd4b996817de4bf1ed67a", "lessThan": "a6d57084372161f86660bc4607784420e00efe2c", "status": "affected", "versionType": "git" }, { "version": "58c9b016e12855286370dfb704c08498edbc857a", "lessThan": "a6566cd33f6f967a7651ebf2ce0dd31572e319cf", "status": "affected", "versionType": "git" }, { "version": "58c9b016e12855286370dfb704c08498edbc857a", "lessThan": "5b1173b165421561db29f30afc7e97d940a398a9", "status": "affected", "versionType": "git" }, { "version": "58c9b016e12855286370dfb704c08498edbc857a", "lessThan": "7e8083f5eeedab0f460063b9c2c14c9a4e71a427", "status": "affected", "versionType": "git" }, { "version": "58c9b016e12855286370dfb704c08498edbc857a", "lessThan": "ae0bb9c1fb7c2594519aeeb096cf2c3b7837b322", "status": "affected", "versionType": "git" }, { "version": "58c9b016e12855286370dfb704c08498edbc857a", "lessThan": "07712db80857d5d09ae08f3df85a708ecfc3b61f", "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/eventpoll.c" ], "versions": [ { "version": "6.4", "status": "affected" }, { "version": "0", "lessThan": "6.4", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.136", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.83", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.24", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.14", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.4", "versionEndExcluding": "6.6.136" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.12.83" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.18.24" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.19.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/902120be4f44947df6311002addc7faf69bdbff1" }, { "url": "https://git.kernel.org/stable/c/a6d57084372161f86660bc4607784420e00efe2c" }, { "url": "https://git.kernel.org/stable/c/a6566cd33f6f967a7651ebf2ce0dd31572e319cf" }, { "url": "https://git.kernel.org/stable/c/5b1173b165421561db29f30afc7e97d940a398a9" }, { "url": "https://git.kernel.org/stable/c/7e8083f5eeedab0f460063b9c2c14c9a4e71a427" }, { "url": "https://git.kernel.org/stable/c/ae0bb9c1fb7c2594519aeeb096cf2c3b7837b322" }, { "url": "https://git.kernel.org/stable/c/07712db80857d5d09ae08f3df85a708ecfc3b61f" } ], "title": "eventpoll: defer struct eventpoll free to RCU grace period", "x_generator": { "engine": "bippy-1.2.0" } } } }