{"id":"CVE-2026-64318","summary":"partitions: aix: bound the pp_count scan to the ppe array","details":"In the Linux kernel, the following vulnerability has been resolved:\n\npartitions: aix: bound the pp_count scan to the ppe array\n\naix_partition() reads the physical volume descriptor into a fixed-size\nstruct pvd and then scans its physical-partition-extent array:\n\n\tint numpps = be16_to_cpu(pvd-\u003epp_count);\n\t...\n\tfor (i = 0; i \u003c numpps; i += 1) {\n\t\tstruct ppe *p = pvd-\u003eppe + i;\n\t\t...\n\t\tlp_ix = be16_to_cpu(p-\u003elp_ix);\n\npvd points at a single kmalloc()'d struct pvd whose ppe[] member holds a\nfixed ARRAY_SIZE(pvd-\u003eppe) (1016) entries, but the loop runs up to the\non-disk pp_count.  pp_count is an unvalidated __be16 read straight from\nthe descriptor, so a crafted AIX image with pp_count larger than 1016\ndrives the loop to read pvd-\u003eppe[i] past the end of the allocation (up\nto 65535 entries, ~2 MB out of bounds).\n\nThe partition scan runs without mounting anything, when a block device\nwith a crafted AIX/IBM partition table appears (an attacker-supplied\nimage attached with losetup -P, or a device auto-scanned by udev), via\nmsdos_partition() -\u003e aix_partition().\n\nClamp the scan to the number of entries the ppe[] array can hold.","modified":"2026-09-05T03:31:10.353272444Z","published":"2026-07-25T08:49:47.690Z","related":["openSUSE-SU-2026:11476-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64318.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/09861651617ba0fec089e8b9477439e68398c110"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2dc0bfd2fe355fb930de63c2f2eb8ced8570c579"},{"type":"WEB","url":"https://git.kernel.org/stable/c/44f37ee92fdcd377c41bdf6a31cdd8cc7d4c410e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4671bb74bba05fdd4acf670a35758c29e8c97b83"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5eacdb1967378f5e5591cd27a2d8cdee2df1a599"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b5e9c09309e18fd9839ad007c238120353ca0cc4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ce93228e2193a17d2c58b656e439bb39fe5c3af8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fd94a779020f2ecc8b2607f4c20b34acb1763b9a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64318.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64318"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6ceea22bbbc84fcf6bf0913bb3db8a657e9002f6"},{"fixed":"09861651617ba0fec089e8b9477439e68398c110"},{"fixed":"5eacdb1967378f5e5591cd27a2d8cdee2df1a599"},{"fixed":"b5e9c09309e18fd9839ad007c238120353ca0cc4"},{"fixed":"fd94a779020f2ecc8b2607f4c20b34acb1763b9a"},{"fixed":"4671bb74bba05fdd4acf670a35758c29e8c97b83"},{"fixed":"ce93228e2193a17d2c58b656e439bb39fe5c3af8"},{"fixed":"44f37ee92fdcd377c41bdf6a31cdd8cc7d4c410e"},{"fixed":"2dc0bfd2fe355fb930de63c2f2eb8ced8570c579"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64318.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.11.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64318.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}