{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74354","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-15T05:44:03.887Z","datePublished":"2026-08-15T05:58:40.067Z","dateUpdated":"2026-08-17T05:46:14.991Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-17T05:46:14.991Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Take mmap_lock in zap_pages()\n\nzap_vma_range() requires the owning mm's mmap_lock to be held.\n\nTaking mmap_read_lock under arena->lock would AB-BA against\narena_vm_close() and arena_map_mmap(), both of which run with\nmmap_write_lock held and then acquire arena->lock. Instead drop\narena->lock, mmget_not_zero() the vma's mm, take mmap_read_lock, and\nre-resolve the vma via find_vma() since it may have been unmapped or\nreplaced while waiting.\n\nTrack processed vmls with a per-call generation in vml->zap_gen and\nserialize zap_pages() callers with a new arena->zap_mutex so\nconcurrent callers on different uaddr ranges do not mark each other's\nvmls processed before the zap is done."}],"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 flaw is reached only via local bpf(2) syscalls: creating a BPF_MAP_TYPE_ARENA, loading a JIT BPF program using bpf_arena_free_pages(), mmap()ing the arena, and executing that program, which calls zap_pages() and zap_vma_range() without mmap_lock.\nAC:L - Exploitation requires racing page unmap with concurrent VMA teardown; the attacker controls both sides by running bpf_arena_free_pages() from BPF while another thread or process concurrently munmap()s or remaps the same arena mapping.\nPR:L - Arena map creation requires CAP_BPF and verifier-enforced CAP_BPF plus CAP_PERFMON (bpf_allow_ptr_leaks), not init-namespace root; these capabilities are obtainable by an unprivileged user via user namespaces or perf-group membership on typical systems.\nUI:N - No victim interaction is required beyond the attacker loading their own BPF program and mmaping their own arena; triggering the race is fully automated once those attacker-controlled setup steps are done.\nS:U - Impact is confined to kernel memory management and process address spaces on the host; it does not cross a VM, container, or IOMMU security boundary into a separate authority such as a hypervisor host escape.\nC:H - Calling zap_vma_range() without mmap_lock races with munmap and page faults, enabling stale VMA use, page-table corruption, and use-after-free conditions that can be leveraged for arbitrary kernel or cross-process memory disclosure.\nI:H - Unsynchronized PTE zapping and rmap updates can corrupt page tables and VMA metadata, providing memory corruption primitives that can be developed into arbitrary kernel writes and control-flow hijacking.\nA:H - The mmap_lock violation can cause kernel oopses, panics, or hung memory management from inconsistent page tables and invalid VMA access during concurrent unmap operations."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/arena.c"],"versions":[{"version":"317460317a02a1af512697e6e964298dedd8a163","lessThan":"36b1d997866f6083d33934983aa2ce0a184ed642","status":"affected","versionType":"git"},{"version":"317460317a02a1af512697e6e964298dedd8a163","lessThan":"80b89d0226a05e8b67969de99c31b51fcd54f76a","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/arena.c"],"versions":[{"version":"6.9","status":"affected"},{"version":"0","lessThan":"6.9","status":"unaffected","versionType":"semver"},{"version":"7.1.5","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","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":"6.9","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/36b1d997866f6083d33934983aa2ce0a184ed642"},{"url":"https://git.kernel.org/stable/c/80b89d0226a05e8b67969de99c31b51fcd54f76a"}],"title":"bpf: Take mmap_lock in zap_pages()","x_generator":{"engine":"bippy-1.2.0"}}}}