{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38102", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.985Z", "datePublished": "2025-07-03T08:35:12.255Z", "dateUpdated": "2026-08-05T11:59:33.071Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:59:33.071Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nVMCI: fix race between vmci_host_setup_notify and vmci_ctx_unset_notify\n\nDuring our test, it is found that a warning can be trigger in try_grab_folio\nas follow:\n\n ------------[ cut here ]------------\n WARNING: CPU: 0 PID: 1678 at mm/gup.c:147 try_grab_folio+0x106/0x130\n Modules linked in:\n CPU: 0 UID: 0 PID: 1678 Comm: syz.3.31 Not tainted 6.15.0-rc5 #163 PREEMPT(undef)\n RIP: 0010:try_grab_folio+0x106/0x130\n Call Trace:\n \n follow_huge_pmd+0x240/0x8e0\n follow_pmd_mask.constprop.0.isra.0+0x40b/0x5c0\n follow_pud_mask.constprop.0.isra.0+0x14a/0x170\n follow_page_mask+0x1c2/0x1f0\n __get_user_pages+0x176/0x950\n __gup_longterm_locked+0x15b/0x1060\n ? gup_fast+0x120/0x1f0\n gup_fast_fallback+0x17e/0x230\n get_user_pages_fast+0x5f/0x80\n vmci_host_unlocked_ioctl+0x21c/0xf80\n RIP: 0033:0x54d2cd\n ---[ end trace 0000000000000000 ]---\n\nDigging into the source, context->notify_page may init by get_user_pages_fast\nand can be seen in vmci_ctx_unset_notify which will try to put_page. However\nget_user_pages_fast is not finished here and lead to following\ntry_grab_folio warning. The race condition is shown as follow:\n\ncpu0\t\t\tcpu1\nvmci_host_do_set_notify\nvmci_host_setup_notify\nget_user_pages_fast(uva, 1, FOLL_WRITE, &context->notify_page);\nlockless_pages_from_mm\ngup_pgd_range\ngup_huge_pmd // update &context->notify_page\n\t\t\tvmci_host_do_set_notify\n\t\t\tvmci_ctx_unset_notify\n\t\t\tnotify_page = context->notify_page;\n\t\t\tif (notify_page)\n\t\t\tput_page(notify_page);\t// page is freed\n__gup_longterm_locked\n__get_user_pages\nfollow_trans_huge_pmd\ntry_grab_folio // warn here\n\nTo slove this, use local variable page to make notify_page can be seen\nafter finish get_user_pages_fast." } ], "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 through `IOCTL_VMCI_SET_NOTIFY` on the `/dev/vmci` character device (`vmci_host_unlocked_ioctl` → `vmci_host_do_set_notify`), which requires local access to the host system. There is no remote or network-facing path into the VMCI host personality.\nAC:L - The attacker controls both sides of the race — two threads issuing `SET_NOTIFY` on the same fd, one with a non-zero `notify_uva` and one with zero — and `vmci_host_do_set_notify` is not serialized by `vmci_host_dev->lock`, so the race can be looped indefinitely. Backing the UVA with a THP widens the window further, since `record_subpages()` in `gup_huge_pmd` publishes the page pointer into `context->notify_page` before the pin is validated.\nPR:L - There is no `capable()`, credential, or privilege check anywhere in `vmci_host_open()`, `vmci_ctx_create()`, or the SET_NOTIFY ioctl path — only the permissions on `/dev/vmci` gate access, and on VMware Workstation/Player hosts that node must be accessible to unprivileged users because the per-user VMX process opens it to create its VMCI context. A normal local user account is therefore sufficient.\nUI:N - Exploitation is entirely self-contained: the attacker opens `/dev/vmci`, issues `INIT_CONTEXT`, and races two `SET_NOTIFY` ioctls from its own threads. No victim action is required.\nS:U - The corruption occurs in host kernel memory and is exploited by a local host user, staying within the kernel's own security authority. Although VMCI is virtualization-related, this is the host-side personality driven by local ioctls, not a guest-to-host boundary crossing.\nC:H - `vmci_ctx_unset_notify()` calls `put_page()` on a pointer that `get_user_pages_fast()` published into `context->notify_page` before taking (or after rolling back) the reference, producing a refcount underflow that frees a page still mapped by userspace and still in use elsewhere. Once that page is recycled into kernel allocations while the attacker retains a user mapping, arbitrary kernel memory can be read.\nI:H - The same premature free gives the attacker a writable userspace mapping of a page the kernel later reallocates, a direct arbitrary-write primitive; additionally `context->notify` is left dangling into a released page and `ctx_signal_notify()` writes `true` through it at an attacker-chosen page offset when a datagram is queued. Both paths are readily leveraged for control-flow hijacking and privilege escalation.\nA:H - The race reliably trips `WARN_ON` in `try_grab_folio` (as reported by syzkaller) and, in the general case, causes page refcount underflow, double-free, and use-after-free of memory still in use, leading to kernel oops or panic. It can be triggered repeatedly by an unprivileged process." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/misc/vmw_vmci/vmci_host.c" ], "versions": [ { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "74095bbbb19ca74a0368d857603a2438c88ca86c", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "468aec888f838ce5174b96e0cb4396790d6f60ca", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "b4209e4b778e4e57d0636e1c9fc07a924dbc6043", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "58a90db70aa6616411e5f69d1982d9b1dd97d774", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "6e3af836805ed1d7a699f76ec798626198917aa4", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "00ddc7dad55b7bbb78df80d6e174d0c4764dea0c", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "75b5313c80c39a26d27cbb602f968a05576c36f9", "status": "affected", "versionType": "git" }, { "version": "a1d88436d53a75e950db15834b3d2f8c0c358fdc", "lessThan": "1bd6406fb5f36c2bb1e96e27d4c3e9f4d09edde4", "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/misc/vmw_vmci/vmci_host.c" ], "versions": [ { "version": "4.0", "status": "affected" }, { "version": "0", "lessThan": "4.0", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.296", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.240", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.186", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.142", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.94", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.34", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.3", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16", "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": "4.0", "versionEndExcluding": "5.4.296" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "5.10.240" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "5.15.186" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.1.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.6.94" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.12.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.15.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0", "versionEndExcluding": "6.16" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/74095bbbb19ca74a0368d857603a2438c88ca86c" }, { "url": "https://git.kernel.org/stable/c/468aec888f838ce5174b96e0cb4396790d6f60ca" }, { "url": "https://git.kernel.org/stable/c/b4209e4b778e4e57d0636e1c9fc07a924dbc6043" }, { "url": "https://git.kernel.org/stable/c/58a90db70aa6616411e5f69d1982d9b1dd97d774" }, { "url": "https://git.kernel.org/stable/c/6e3af836805ed1d7a699f76ec798626198917aa4" }, { "url": "https://git.kernel.org/stable/c/00ddc7dad55b7bbb78df80d6e174d0c4764dea0c" }, { "url": "https://git.kernel.org/stable/c/75b5313c80c39a26d27cbb602f968a05576c36f9" }, { "url": "https://git.kernel.org/stable/c/1bd6406fb5f36c2bb1e96e27d4c3e9f4d09edde4" } ], "title": "VMCI: fix race between vmci_host_setup_notify and vmci_ctx_unset_notify", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:34:05.919Z" } } ] } }