{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-46065", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-13T15:03:33.095Z", "datePublished": "2026-05-27T12:57:32.968Z", "dateUpdated": "2026-08-05T12:29:27.785Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:29:27.785Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info\n\nHold state of deferred I/O in struct fb_deferred_io_state. Allocate an\ninstance as part of initializing deferred I/O and remove it only after\nthe final mapping has been closed. If the fb_info and the contained\ndeferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info\nto invalidate the mapping. Any access will then result in a SIGBUS\nsignal.\n\nFixes a long-standing problem, where a device hot-unplug happens while\nuser space still has an active mapping of the graphics memory. The hot-\nunplug frees the instance of struct fb_info. Accessing the memory will\noperate on undefined state." } ], "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 fault handlers are reached by mmap'ing /dev/fbN and accessing the mapping — a local operation requiring no network. Device removal (the precondition) can be non-physical (VM host-driven removal, sysfs unbind, module unload), so Local is the most severe defensible vector over Physical.\nAC:L - Once the device is removed while a mapping is active, any access deterministically hits the freed defio state/video pages — no race must be won to trigger it. In a kiosk/embedded scenario with a removable display the attacker controls both the mapping and the removal, and heap reclaim is attacker-influenced.\nPR:L - Exploitation requires only a local user with access to the framebuffer device, which is granted to the logged-in/console user, video-group members, Android apps, and is often world-accessible on embedded/kiosk systems. No root or init-namespace privilege is needed.\nUI:N - The attacker performs all steps themselves — map the framebuffer, cause/await removal, then access the mapping — with no separate victim action required.\nS:U - The use-after-free corrupts kernel memory within the same security authority; even in the VM-framebuffer case the impact stays inside the guest kernel and does not cross into the hypervisor.\nC:H - The fault handler returns freed-and-reclaimed video pages and the freed pagerefs array to userspace, allowing disclosure of arbitrary reallocated kernel/user memory — a use-after-free read primitive.\nI:H - The write-fault path writes a page pointer and offset into the kvfree'd pagerefs array and exposes freed/reallocated pages for writing, giving a use-after-free write primitive usable for control-flow hijacking via heap spraying.\nA:H - Accessing the mapping after teardown uses a destroyed mutex, freed pagerefs, and hits BUG_ON(!info->fbdefio->mapping), reliably causing an oops/panic; any use-after-free crashes the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/video/fbdev/core/fb_defio.c", "include/linux/fb.h" ], "versions": [ { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "4aab89603b637a2e441b38808c4f6fe7d1184df6", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "4fda0d6b45faad44926dd3e4f55f118d899b2e27", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "2a40f8bc9bb713329f1c35ffc199ee961a7135b0", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "2b53d3a52e8e5403a4f4fb57ac6cad3fd2cb1066", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "25c2b77bc463f29ee71a54b883548baf9386a0db", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "a0aafb421dd15e935d81543152617f2742cefa70", "status": "affected", "versionType": "git" }, { "version": "60b59beafba875aef6d378078bce0baf2287ae14", "lessThan": "9ded47ad003f09a94b6a710b5c47f4aa5ceb7429", "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/video/fbdev/core/fb_defio.c", "include/linux/fb.h" ], "versions": [ { "version": "2.6.22", "status": "affected" }, { "version": "0", "lessThan": "2.6.22", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.140", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.88", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.30", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.4", "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": "2.6.22", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "6.6.140" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "6.12.88" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "6.18.30" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "7.0.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.22", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/4aab89603b637a2e441b38808c4f6fe7d1184df6" }, { "url": "https://git.kernel.org/stable/c/4fda0d6b45faad44926dd3e4f55f118d899b2e27" }, { "url": "https://git.kernel.org/stable/c/2a40f8bc9bb713329f1c35ffc199ee961a7135b0" }, { "url": "https://git.kernel.org/stable/c/2b53d3a52e8e5403a4f4fb57ac6cad3fd2cb1066" }, { "url": "https://git.kernel.org/stable/c/25c2b77bc463f29ee71a54b883548baf9386a0db" }, { "url": "https://git.kernel.org/stable/c/a0aafb421dd15e935d81543152617f2742cefa70" }, { "url": "https://git.kernel.org/stable/c/9ded47ad003f09a94b6a710b5c47f4aa5ceb7429" } ], "title": "fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info", "x_generator": { "engine": "bippy-1.2.0" } } } }