{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-89777", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-89777", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-09-16T08:48:17.754Z", "updatedAt": "2026-10-19T08:52:29.546Z", "importedAt": "2026-10-24T01:58:35.090Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "vfio/pci: clear vdev->msi_perm after freeing it on init failure", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/pci: clear vdev->msi_perm after freeing it on init failure\n\nvfio_msi_cap_len() lazily allocates the per-device MSI permission table:\n\n\tvdev->msi_perm = kmalloc_obj(struct perm_bits, GFP_KERNEL_ACCOUNT);\n\tif (!vdev->msi_perm)\n\t\treturn -ENOMEM;\n\n\tret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags);\n\tif (ret) {\n\t\tkfree(vdev->msi_perm);\n\t\treturn ret;\t\t/* vdev->msi_perm left dangling */\n\t}\n\nWhen init_pci_cap_msi_perm() -> alloc_perm_bits() fails with -ENOMEM, the\nerror path frees vdev->msi_perm but leaves the freed pointer stored in\nit. vdev->msi_perm is not re-zeroed later because struct\nvfio_pci_core_device is per-device and persists across open/close cycles,\nand the vfio_config_init() error path returns without calling\nvfio_config_free(). So the dangling pointer outlives the failed open.\n\nThat leads to two use-after-frees on the same device:\n\n1. Reuse. The next vfio_config_init() sees the stale pointer at\n \"if (vdev->msi_perm) return len;\" and reuses the freed object. MSI\n config accesses in vfio_pci_config_rw_single() then dereference and\n call the freed perm->readfn / perm->writefn function pointers.\n\n2. Double free. A later vfio_config_free() runs free_perm_bits() and\n kfree() on the already-freed object.\n\nFix it by NULLing vdev->msi_perm after the kfree(), matching the\nNULL-after-free discipline already used in free_perm_bits() and\nvfio_config_free().\n\n BUG: KASAN: slab-use-after-free in vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)\n Read of size 8 at addr ffff88800fcc88d0 by task exploit/143\n Call Trace:\n ...\n kasan_report (mm/kasan/report.c:595)\n vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)\n vfio_pci_config_rw (drivers/vfio/pci/vfio_pci_config.c:1986)\n vfio_pci_rw (drivers/vfio/pci/vfio_pci_core.c:1599)\n vfs_read (fs/read_write.c:572)\n __x64_sys_pread64 (fs/read_write.c:764)\n do_syscall_64 (arch/x86/entry/syscall_64.c:94)\n ...\n\nFollowed on device close by a double free of the same object:\n\n Oops: general protection fault, probably for non-canonical address\n 0x1f63e0e8000008: 0000 [#1] SMP KASAN NOPTI\n RIP: 0010:kfree (mm/slub.c:6711)\n Call Trace:\n vfio_config_free (drivers/vfio/pci/vfio_pci_config.c:1861)\n vfio_pci_core_disable (drivers/vfio/pci/vfio_pci_core.c:685)\n vfio_pci_core_close_device (drivers/vfio/pci/vfio_pci_core.c:777)\n vfio_df_close (drivers/vfio/vfio_main.c:602)\n vfio_device_fops_release (drivers/vfio/vfio_main.c:648)\n __fput (fs/file_table.c:512)\n __x64_sys_close (fs/open.c:1496)\n do_syscall_64 (arch/x86/entry/syscall_64.c:94)\n ...\n Kernel panic - not syncing: Fatal exception", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "eb84cd81040e58dd05ac190f561f2115e3367249" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "f0eea8f9013676b42289ec35941e848b8a543e19" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "d665a1688af7f8fefd7c0eb04f2a37122ce007f4" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "25cdd2a492d868cff1e519a60fe282909c52d385" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "812f1db7f0755a19ef16ecdc5cec51bcabc5eda5" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "533d0c5feef85ee6404b9f41d5564fac6971a008" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "fda8fb7e8179561693a786a7af593f6b944a21c1" }, { "version": "30ea32ab1951c80c6113f300fce2c70cd12659e4", "status": "affected", "versionType": "git", "lessThan": "dc77acfeb979dded39b247b60fef0399536bfa77" }, { "version": "ac370e3d1f3b01519d2705cd5815d1c9d0a8812b", "status": "affected", "versionType": "git" }, { "version": "be363e27ec3c3a99793da2be6c07eafb95709c6b", "status": "affected", "versionType": "git" }, { "version": "f1b10ba5739440ca51d66f0b2949cead88d2dd02", "status": "affected", "versionType": "git" }, { "version": "dde3433de9a067a33d67d65b9093cad3e043e49e", "status": "affected", "versionType": "git" }, { "version": "4.4.203", "status": "affected", "versionType": "semver", "lessThan": "4.5" }, { "version": "4.9.203", "status": "affected", "versionType": "semver", "lessThan": "4.10" }, { "version": "4.14.155", "status": "affected", "versionType": "semver", "lessThan": "4.15" }, { "version": "4.19.85", "status": "affected", "versionType": "semver", "lessThan": "4.20" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.20", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.20" }, { "version": "5.10.270", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.221", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.188", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.157", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.110", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.52", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.2.6", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.2.*" }, { "version": "7.3", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }