{"id":"CVE-2026-64426","state":"PUBLISHED","title":"io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/nop: fix file reference leak with IOSQE_FIXED_FILE\n\nNOP file-acquisition support choses between a fixed (registered) file and\na normal fget()'d file based on its own IORING_NOP_FIXED_FILE flag in\nsqe->nop_flags. However, a request's REQ_F_FIXED_FILE is set\nindependently from the generic IOSQE_FIXED_FILE sqe flag during request\ninit, before the issue handler runs.\n\nIf a NOP is submitted with IOSQE_FIXED_FILE set (so REQ_F_FIXED_FILE is\nset) but without IORING_NOP_FIXED_FILE, io_nop() takes the normal path\nand grabs a real reference via io_file_get_normal(). On completion,\nio_put_file() only drops the reference when REQ_F_FIXED_FILE is clear,\nso the fget()'d file is never released and leaks:\n\n  BUG: memory leak\n  unreferenced object 0xffff88800f42c240 (size 176):\n    kmem_cache_alloc_noprof+0x358/0x440\n    alloc_empty_file+0x57/0x180\n    path_openat+0x44/0x1e50\n    do_file_open+0x121/0x200\n    do_sys_openat2+0xa7/0x150\n    __x64_sys_openat+0x82/0xf0\n\nDecide between fixed and normal file acquisition from REQ_F_FIXED_FILE,\nthe same way io_assign_file() does for every other opcode, and fold\nIORING_NOP_FIXED_FILE into REQ_F_FIXED_FILE at prep time.","publishedAt":"2026-07-25T08:51:03.867Z","updatedAt":"2026-08-17T04:55:26.542Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"722869fcff598fad20d5ab79c305897a7534708b","versionType":"git"},{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"7267717f35787167fcce4bc14f6ef3fa06682dcf","versionType":"git"},{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"2564ca2e31bd8ee8348362941af2ee4671e487ca","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["io_uring/nop.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["io_uring/nop.c"]}],"references":["https://git.kernel.org/stable/c/722869fcff598fad20d5ab79c305897a7534708b","https://git.kernel.org/stable/c/7267717f35787167fcce4bc14f6ef3fa06682dcf","https://git.kernel.org/stable/c/2564ca2e31bd8ee8348362941af2ee4671e487ca"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64426.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64426","state":"PUBLISHED","datePublished":"2026-07-25T08:51:03.867Z","dateUpdated":"2026-08-17T04:55:26.542Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.787Z"},"containers":{"cna":{"title":"io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/nop: fix file reference leak with IOSQE_FIXED_FILE\n\nNOP file-acquisition support choses between a fixed (registered) file and\na normal fget()'d file based on its own IORING_NOP_FIXED_FILE flag in\nsqe->nop_flags. However, a request's REQ_F_FIXED_FILE is set\nindependently from the generic IOSQE_FIXED_FILE sqe flag during request\ninit, before the issue handler runs.\n\nIf a NOP is submitted with IOSQE_FIXED_FILE set (so REQ_F_FIXED_FILE is\nset) but without IORING_NOP_FIXED_FILE, io_nop() takes the normal path\nand grabs a real reference via io_file_get_normal(). On completion,\nio_put_file() only drops the reference when REQ_F_FIXED_FILE is clear,\nso the fget()'d file is never released and leaks:\n\n  BUG: memory leak\n  unreferenced object 0xffff88800f42c240 (size 176):\n    kmem_cache_alloc_noprof+0x358/0x440\n    alloc_empty_file+0x57/0x180\n    path_openat+0x44/0x1e50\n    do_file_open+0x121/0x200\n    do_sys_openat2+0xa7/0x150\n    __x64_sys_openat+0x82/0xf0\n\nDecide between fixed and normal file acquisition from REQ_F_FIXED_FILE,\nthe same way io_assign_file() does for every other opcode, and fold\nIORING_NOP_FIXED_FILE into REQ_F_FIXED_FILE at prep time."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"722869fcff598fad20d5ab79c305897a7534708b","versionType":"git"},{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"7267717f35787167fcce4bc14f6ef3fa06682dcf","versionType":"git"},{"version":"a85f31052bce52111b4e9d5a536003481d0421d0","status":"affected","lessThan":"2564ca2e31bd8ee8348362941af2ee4671e487ca","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["io_uring/nop.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["io_uring/nop.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/722869fcff598fad20d5ab79c305897a7534708b"},{"url":"https://git.kernel.org/stable/c/7267717f35787167fcce4bc14f6ef3fa06682dcf"},{"url":"https://git.kernel.org/stable/c/2564ca2e31bd8ee8348362941af2ee4671e487ca"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:55:26.542Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}