CVE-2026-74481

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74481", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.904Z", "datePublished": "2026-08-15T12:27:14.441Z", "dateUpdated": "2026-10-16T19:05:48.983Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:37:36.090Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_reporting: use system_freezable_wq to fix UAF during suspend\n\nDuring PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like\nvirtio_balloon reset their underlying virtio devices and delete their\nvirtqueues via vdev->config->del_vqs().\n\nHowever, page reporting work (page_reporting_process) was scheduled on the\nglobal system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM\nfreezer skips it, leaving page_reporting_process active during suspend.\n\nIf pages are freed into the buddy allocator while suspending (for example,\nwhen core MM invokes the balloon shrinker during S4 hibernation image\nsaving), page reporting triggers virtballoon_free_page_report() on deleted\nvirtqueues, resulting in a Use-After-Free / General Protection Fault:\n\n [ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI\n [ 196.825967] Workqueue: events page_reporting_process\n [ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring]\n [ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon]\n [ 196.946943] page_reporting_process+0x370/0x4f0\n\nFix this by switching page reporting work to system_freezable_wq. This\nensures that the PM freezer pauses page_reporting_process before device\ndrivers destroy their reporting virtqueues. Because the reporting worker\nis frozen, memory reclamation/freeing (e.g. via shrinker execution) can\nsafely return pages to MM during freeze without triggering unfrozen\nreporting work on deleted virtqueues.\n\nThis aligns with the driver's existing design. The comment in\nvirtballoon_freeze() states:\n /*\n * The workqueue is already frozen by the PM core before this\n * function is called.\n */\n\nTesting:\nI have verified these fixes using Google\u2019s virtualization infrastructure\nby running continuous suspend/resume iterations (40+ cycles) while\nchurning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60%\n--timeout 1`) to constantly create free pages for the buddy allocator. We\nalso set the `page_reporting_order` parameter to 0 to make the page\nreporting worker highly sensitive, forcing it to pick up any 4K free\npages. This confirmed that the UAF crashes are no longer reproducible."}], "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 UAF is reached only through local PM suspend/hibernation and guest memory-free paths (__free_one_page -> page_reporting_notify_free -> page_reporting_process -> virtballoon_free_page_report); it is not reachable via network protocols or remote packet handling.\nAC:L - An attacker with local access can reliably drive the race by churning memory (e.g. stress-ng) to flood page-reporting work while triggering or awaiting S3/S4 suspend, as demonstrated in the fix commit's reproduction on virtio-balloon VMs.\nPR:L - No real-root capability is required to exercise the memory-free entry path (normal unprivileged mmap/malloc/free syscalls), and many desktop deployments allow session users to initiate suspend via logind/polkit without full init-namespace root.\nUI:N - Exploitation does not require a separate victim action beyond the attacker (or system policy) initiating suspend/hibernation; automated cloud/VM suspend-resume cycles and scripted PM transitions suffice without interactive victim cooperation.\nS:U - Impact is confined to guest kernel memory corruption and crash inside the virtio-balloon/page-reporting subsystem; it does not cross a VM/host, IOMMU, or sandbox security boundary to affect resources outside the kernel's own authority.\nC:H - This is a kernel heap use-after-free on freed virtqueue metadata accessed through virtqueue_add_split; UAF of kernel objects can be leveraged for arbitrary kernel memory read/info disclosure beyond the observed GPF crash.\nI:H - UAF on virtqueue/vring kernel structures during virtqueue_add_split provides a memory-corruption primitive that can be developed into controlled kernel writes or code execution, not merely a benign crash.\nA:H - The bug provably causes a kernel general protection fault/oops in page_reporting_process during suspend (Workqueue: events), crashing or destabilizing the system and denying availability on every affected suspend/hibernation cycle."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/page_reporting.c"], "versions": [{"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "a4c60046052777ca1dcc83fe3ece2a5136b301f1", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "b2c094e98f8bb823b3ae475f7169fe2091c40c6d", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "992f270fd808338fbae1f498a5e325e7e2e20368", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "f978048326570047e8216e81a67f9c71ef2bb1b1", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "450f35f4d5a682a0796757e52295df58ddb63bc9", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "b11907c905fa08eda925395f0724b7a409870f65", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7", "status": "affected", "versionType": "git"}, {"version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "0b45f6927a14914ff685fe0e6f9d11232a1e03df", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/page_reporting.c"], "versions": [{"version": "5.7", "status": "affected"}, {"version": "0", "lessThan": "5.7", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.151", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.103", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.44", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.8", "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": "5.7", "versionEndExcluding": "5.10.265"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "5.15.216"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.1.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.6.151"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.12.103"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.18.44"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.1.8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a4c60046052777ca1dcc83fe3ece2a5136b301f1"}, {"url": "https://git.kernel.org/stable/c/b2c094e98f8bb823b3ae475f7169fe2091c40c6d"}, {"url": "https://git.kernel.org/stable/c/992f270fd808338fbae1f498a5e325e7e2e20368"}, {"url": "https://git.kernel.org/stable/c/f978048326570047e8216e81a67f9c71ef2bb1b1"}, {"url": "https://git.kernel.org/stable/c/450f35f4d5a682a0796757e52295df58ddb63bc9"}, {"url": "https://git.kernel.org/stable/c/b11907c905fa08eda925395f0724b7a409870f65"}, {"url": "https://git.kernel.org/stable/c/faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7"}, {"url": "https://git.kernel.org/stable/c/0b45f6927a14914ff685fe0e6f9d11232a1e03df"}], "title": "mm/page_reporting: use system_freezable_wq to fix UAF during suspend", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-74481", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T18:57:45.101951Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:05:48.983Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-74481", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T18:57:45.101951Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T18:57:45.958Z"}}], "cna": {"title": "mm/page_reporting: use system_freezable_wq to fix UAF during suspend", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 7.8, "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:L - The UAF is reached only through local PM suspend/hibernation and guest memory-free paths (__free_one_page -> page_reporting_notify_free -> page_reporting_process -> virtballoon_free_page_report); it is not reachable via network protocols or remote packet handling.\nAC:L - An attacker with local access can reliably drive the race by churning memory (e.g. stress-ng) to flood page-reporting work while triggering or awaiting S3/S4 suspend, as demonstrated in the fix commit's reproduction on virtio-balloon VMs.\nPR:L - No real-root capability is required to exercise the memory-free entry path (normal unprivileged mmap/malloc/free syscalls), and many desktop deployments allow session users to initiate suspend via logind/polkit without full init-namespace root.\nUI:N - Exploitation does not require a separate victim action beyond the attacker (or system policy) initiating suspend/hibernation; automated cloud/VM suspend-resume cycles and scripted PM transitions suffice without interactive victim cooperation.\nS:U - Impact is confined to guest kernel memory corruption and crash inside the virtio-balloon/page-reporting subsystem; it does not cross a VM/host, IOMMU, or sandbox security boundary to affect resources outside the kernel's own authority.\nC:H - This is a kernel heap use-after-free on freed virtqueue metadata accessed through virtqueue_add_split; UAF of kernel objects can be leveraged for arbitrary kernel memory read/info disclosure beyond the observed GPF crash.\nI:H - UAF on virtqueue/vring kernel structures during virtqueue_add_split provides a memory-corruption primitive that can be developed into controlled kernel writes or code execution, not merely a benign crash.\nA:H - The bug provably causes a kernel general protection fault/oops in page_reporting_process during suspend (Workqueue: events), crashing or destabilizing the system and denying availability on every affected suspend/hibernation cycle."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "a4c60046052777ca1dcc83fe3ece2a5136b301f1", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "b2c094e98f8bb823b3ae475f7169fe2091c40c6d", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "992f270fd808338fbae1f498a5e325e7e2e20368", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "f978048326570047e8216e81a67f9c71ef2bb1b1", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "450f35f4d5a682a0796757e52295df58ddb63bc9", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "b11907c905fa08eda925395f0724b7a409870f65", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7", "versionType": "git"}, {"status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "lessThan": "0b45f6927a14914ff685fe0e6f9d11232a1e03df", "versionType": "git"}], "programFiles": ["mm/page_reporting.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.7"}, {"status": "unaffected", "version": "0", "lessThan": "5.7", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.265", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.216", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.183", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.151", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.103", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.44", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.8", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["mm/page_reporting.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/a4c60046052777ca1dcc83fe3ece2a5136b301f1"}, {"url": "https://git.kernel.org/stable/c/b2c094e98f8bb823b3ae475f7169fe2091c40c6d"}, {"url": "https://git.kernel.org/stable/c/992f270fd808338fbae1f498a5e325e7e2e20368"}, {"url": "https://git.kernel.org/stable/c/f978048326570047e8216e81a67f9c71ef2bb1b1"}, {"url": "https://git.kernel.org/stable/c/450f35f4d5a682a0796757e52295df58ddb63bc9"}, {"url": "https://git.kernel.org/stable/c/b11907c905fa08eda925395f0724b7a409870f65"}, {"url": "https://git.kernel.org/stable/c/faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7"}, {"url": "https://git.kernel.org/stable/c/0b45f6927a14914ff685fe0e6f9d11232a1e03df"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_reporting: use system_freezable_wq to fix UAF during suspend\n\nDuring PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like\nvirtio_balloon reset their underlying virtio devices and delete their\nvirtqueues via vdev->config->del_vqs().\n\nHowever, page reporting work (page_reporting_process) was scheduled on the\nglobal system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM\nfreezer skips it, leaving page_reporting_process active during suspend.\n\nIf pages are freed into the buddy allocator while suspending (for example,\nwhen core MM invokes the balloon shrinker during S4 hibernation image\nsaving), page reporting triggers virtballoon_free_page_report() on deleted\nvirtqueues, resulting in a Use-After-Free / General Protection Fault:\n\n [ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI\n [ 196.825967] Workqueue: events page_reporting_process\n [ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring]\n [ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon]\n [ 196.946943] page_reporting_process+0x370/0x4f0\n\nFix this by switching page reporting work to system_freezable_wq. This\nensures that the PM freezer pauses page_reporting_process before device\ndrivers destroy their reporting virtqueues. Because the reporting worker\nis frozen, memory reclamation/freeing (e.g. via shrinker execution) can\nsafely return pages to MM during freeze without triggering unfrozen\nreporting work on deleted virtqueues.\n\nThis aligns with the driver's existing design. The comment in\nvirtballoon_freeze() states:\n /*\n * The workqueue is already frozen by the PM core before this\n * function is called.\n */\n\nTesting:\nI have verified these fixes using Google\u2019s virtualization infrastructure\nby running continuous suspend/resume iterations (40+ cycles) while\nchurning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60%\n--timeout 1`) to constantly create free pages for the buddy allocator. We\nalso set the `page_reporting_order` parameter to 0 to make the page\nreporting worker highly sensitive, forcing it to pick up any 4K free\npages. This confirmed that the UAF crashes are no longer reproducible."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.265", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.216", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.183", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.151", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.103", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.44", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1.8", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.2", "versionStartIncluding": "5.7"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:37:36.090Z"}}}, "cveMetadata": {"cveId": "CVE-2026-74481", "state": "PUBLISHED", "dateUpdated": "2026-10-16T19:05:48.983Z", "dateReserved": "2026-08-15T05:44:03.904Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-08-15T12:27:14.441Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["mm/page_reporting.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a4c60046052777ca1dcc83fe3ece2a5136b301f1", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "b2c094e98f8bb823b3ae475f7169fe2091c40c6d", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "992f270fd808338fbae1f498a5e325e7e2e20368", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "f978048326570047e8216e81a67f9c71ef2bb1b1", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "450f35f4d5a682a0796757e52295df58ddb63bc9", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "b11907c905fa08eda925395f0724b7a409870f65", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}, {"lessThan": "0b45f6927a14914ff685fe0e6f9d11232a1e03df", "status": "affected", "version": "36e66c554b5c6a9d17a229faca7a61693527b0bd", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["mm/page_reporting.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.7"}, {"lessThan": "5.7", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.265", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.216", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.183", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.151", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.103", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.44", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.8", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_reporting: use system_freezable_wq to fix UAF during suspend\n\nDuring PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like\nvirtio_balloon reset their underlying virtio devices and delete their\nvirtqueues via vdev->config->del_vqs().\n\nHowever, page reporting work (page_reporting_process) was scheduled on the\nglobal system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM\nfreezer skips it, leaving page_reporting_process active during suspend.\n\nIf pages are freed into the buddy allocator while suspending (for example,\nwhen core MM invokes the balloon shrinker during S4 hibernation image\nsaving), page reporting triggers virtballoon_free_page_report() on deleted\nvirtqueues, resulting in a Use-After-Free / General Protection Fault:\n\n [ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI\n [ 196.825967] Workqueue: events page_reporting_process\n [ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring]\n [ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon]\n [ 196.946943] page_reporting_process+0x370/0x4f0\n\nFix this by switching page reporting work to system_freezable_wq. This\nensures that the PM freezer pauses page_reporting_process before device\ndrivers destroy their reporting virtqueues. Because the reporting worker\nis frozen, memory reclamation/freeing (e.g. via shrinker execution) can\nsafely return pages to MM during freeze without triggering unfrozen\nreporting work on deleted virtqueues.\n\nThis aligns with the driver's existing design. The comment in\nvirtballoon_freeze() states:\n /*\n * The workqueue is already frozen by the PM core before this\n * function is called.\n */\n\nTesting:\nI have verified these fixes using Google\u2019s virtualization infrastructure\nby running continuous suspend/resume iterations (40+ cycles) while\nchurning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60%\n--timeout 1`) to constantly create free pages for the buddy allocator. We\nalso set the `page_reporting_order` parameter to 0 to make the page\nreporting worker highly sensitive, forcing it to pick up any 4K free\npages. This confirmed that the UAF crashes are no longer reproducible."}], "id": "CVE-2026-74481", "lastModified": "2026-10-16T20:17:31.093", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-74481", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T18:57:45.101951Z", "version": "2.0.3"}}]}, "published": "2026-08-15T13:17:52.930", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0b45f6927a14914ff685fe0e6f9d11232a1e03df"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/450f35f4d5a682a0796757e52295df58ddb63bc9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/992f270fd808338fbae1f498a5e325e7e2e20368"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a4c60046052777ca1dcc83fe3ece2a5136b301f1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b11907c905fa08eda925395f0724b7a409870f65"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b2c094e98f8bb823b3ae475f7169fe2091c40c6d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f978048326570047e8216e81a67f9c71ef2bb1b1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: mm/page_reporting: use system_freezable_wq to fix UAF during suspend", "id": "2517047", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2517047"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nmm/page_reporting: use system_freezable_wq to fix UAF during suspend\nDuring PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like\nvirtio_balloon reset their underlying virtio devices and delete their\nvirtqueues via vdev->config->del_vqs().\nHowever, page reporting work (page_reporting_process) was scheduled on the\nglobal system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM\nfreezer skips it, leaving page_reporting_process active during suspend.\nIf pages are freed into the buddy allocator while suspending (for example,\nwhen core MM invokes the balloon shrinker during S4 hibernation image\nsaving), page reporting triggers virtballoon_free_page_report() on deleted\nvirtqueues, resulting in a Use-After-Free / General Protection Fault:\n[ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI\n[ 196.825967] Workqueue: events page_reporting_process\n[ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring]\n[ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon]\n[ 196.946943] page_reporting_process+0x370/0x4f0\nFix this by switching page reporting work to system_freezable_wq. This\nensures that the PM freezer pauses page_reporting_process before device\ndrivers destroy their reporting virtqueues. Because the reporting worker\nis frozen, memory reclamation/freeing (e.g. via shrinker execution) can\nsafely return pages to MM during freeze without triggering unfrozen\nreporting work on deleted virtqueues.\nThis aligns with the driver's existing design. The comment in\nvirtballoon_freeze() states:\n/*\n* The workqueue is already frozen by the PM core before this\n* function is called.\n*/\nTesting:\nI have verified these fixes using Google\u2019s virtualization infrastructure\nby running continuous suspend/resume iterations (40+ cycles) while\nchurning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60%\n--timeout 1`) to constantly create free pages for the buddy allocator. We\nalso set the `page_reporting_order` parameter to 0 to make the page\nreporting worker highly sensitive, forcing it to pick up any 4K free\npages. This confirmed that the UAF crashes are no longer reproducible.", "A flaw was found in the Linux kernel's memory management, specifically within the page reporting mechanism. During system suspend or hibernation, the page reporting process could attempt to access memory that had already been freed by device drivers. This Use-After-Free vulnerability can lead to a General Protection Fault, causing a system crash and resulting in a denial of service."], "name": "CVE-2026-74481", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-08-15T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-74481\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-74481\nhttps://lore.kernel.org/linux-cve-announce/2026081536-CVE-2026-74481-ee86@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[36e66c554b5c6a9d17a229faca7a61693527b0bd,f978048326570047e8216e81a67f9c71ef2bb1b1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[36e66c554b5c6a9d17a229faca7a61693527b0bd,450f35f4d5a682a0796757e52295df58ddb63bc9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[36e66c554b5c6a9d17a229faca7a61693527b0bd,b11907c905fa08eda925395f0724b7a409870f65)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[36e66c554b5c6a9d17a229faca7a61693527b0bd,faf439b5fa7b231120eac4f7a617e0bfd4f6f5c7)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[36e66c554b5c6a9d17a229faca7a61693527b0bd,0b45f6927a14914ff685fe0e6f9d11232a1e03df)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.7"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,5.7)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.151,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.103,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.44,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.8,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc6,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-15T15:45:06.744817+00:00", "updated": "2026-08-21T23:00:14.822870+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}