{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-80553", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.766Z", "datePublished": "2026-08-26T14:37:21.774Z", "dateUpdated": "2026-10-16T19:26:26.626Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-27T12:40:13.853Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/vfio_ccw: Cancel existing workqueues\n\nThe initialization of the io_work and crw_work workqueues begs the\nquestion of whether they should be un-initialized. Add the corresponding\ncleanup tags in _release_dev to ensure work isn't dispatched after\nthe private struct is free'd." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached only through local VFIO mediated-device syscalls (read/write/ioctl on /dev/vfio/* and device fds) that start channel I/O or receive CRW events; vfio-ccw has no network, Bluetooth, or physical-bus packet entry point.\nAC:L - This is a close/teardown versus workqueue race where the VFIO client controls both sides: it can submit I/O that queues io_work/crw_work via interrupts or path events, then close or release the device while work is still pending, and retry to win reliably.\nPR:L - Exploitation requires access to an opened vfio-ccw mdev (typical QEMU/libvirt VM operator or delegated /dev/vfio holder on an IBM Z passthrough host), not init-namespace root; mdev creation is admin setup, but triggering the UAF needs only the delegated VFIO fd.\nUI:N - No separate victim action is required; once vfio-ccw passthrough is configured, the attacker issues channel I/O and coordinates device close/release (e.g., hot-unplug or fd teardown) without needing another user to mount media or click anything.\nS:C - On IBM Z/LinuxONE, vfio-ccw exists to pass DASD subchannels into KVM guests; guest-driven channel I/O causes host interrupt/workqueue activity and host-side teardown UAF corrupts hypervisor kernel memory outside the VM security boundary.\nC:H - vfio_ccw_sch_io_todo() and vfio_ccw_crw_todo() dereference freed vfio_ccw_private fields (io_mutex, cp, io_region, crw list, eventfd pointers); per kernel UAF guidance this enables attacker-influenced reuse and arbitrary kernel read primitives.\nI:H - The UAF handlers perform mutex operations, cp_free(), memcpy into io_region, and eventfd_signal() on freed memory, giving heap-sprayable arbitrary write and control-flow hijack potential beyond a simple crash.\nA:H - Use-after-free in deferred I/O/CRW work during device close or release can immediately oops or panic the host kernel from invalid mutex/structure access, and successful exploitation can hang or crash the system even when not leveraged for code execution." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/s390/cio/vfio_ccw_ops.c" ], "versions": [ { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "87d569cb35a541b31a184faf982540694d4c9a89", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "7492ca2d0c5d59add01e267be9f5a6eeb8076fd7", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "b94b28c1f0fae53b2f2d6180ae6442c9a1558f67", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "e868ea8be0bc88c6982f48ecf3259d98afd884ae", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "dc47a98abe6714577a25224534dbd356051097a3", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "b7ae0f7993867d009a4b554fc1d6d451c10580a0", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "77f5e888d2e607a0b3141fb95091ad6ef1cca9a2", "status": "affected", "versionType": "git" }, { "version": "e5f84dbaea59b4f712dac428c337528b70e1c533", "lessThan": "79c60b2c61105368dcc8444eb45847e21734f7c4", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/s390/cio/vfio_ccw_ops.c" ], "versions": [ { "version": "4.12", "status": "affected" }, { "version": "0", "lessThan": "4.12", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.267", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.218", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.185", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.153", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.105", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.46", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.10", "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": "4.12", "versionEndExcluding": "5.10.267" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "5.15.218" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.1.185" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.6.153" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.12.105" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.18.46" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.1.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/87d569cb35a541b31a184faf982540694d4c9a89" }, { "url": "https://git.kernel.org/stable/c/7492ca2d0c5d59add01e267be9f5a6eeb8076fd7" }, { "url": "https://git.kernel.org/stable/c/b94b28c1f0fae53b2f2d6180ae6442c9a1558f67" }, { "url": "https://git.kernel.org/stable/c/e868ea8be0bc88c6982f48ecf3259d98afd884ae" }, { "url": "https://git.kernel.org/stable/c/dc47a98abe6714577a25224534dbd356051097a3" }, { "url": "https://git.kernel.org/stable/c/b7ae0f7993867d009a4b554fc1d6d451c10580a0" }, { "url": "https://git.kernel.org/stable/c/77f5e888d2e607a0b3141fb95091ad6ef1cca9a2" }, { "url": "https://git.kernel.org/stable/c/79c60b2c61105368dcc8444eb45847e21734f7c4" } ], "title": "s390/vfio_ccw: Cancel existing workqueues", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-80553", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:17:19.506995Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:26.626Z" } } ] } }