{"id":"CVE-2025-71072","state":"PUBLISHED","title":"shmem: fix recovery on rename failures","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nshmem: fix recovery on rename failures\n\nmaple_tree insertions can fail if we are seriously short on memory;\nsimple_offset_rename() does not recover well if it runs into that.\nThe same goes for simple_offset_rename_exchange().\n\nMoreover, shmem_whiteout() expects that if it succeeds, the caller will\nprogress to d_move(), i.e. that shmem_rename2() won't fail past the\nsuccessful call of shmem_whiteout().\n\nNot hard to fix, fortunately - mtree_store() can't fail if the index we\nare trying to store into is already present in the tree as a singleton.\n\nFor simple_offset_rename_exchange() that's enough - we just need to be\ncareful about the order of operations.\n\nFor simple_offset_rename() solution is to preinsert the target into the\ntree for new_dir; the rest can be done without any potentially failing\noperations.\n\nThat preinsertion has to be done in shmem_rename2() rather than in\nsimple_offset_rename() itself - otherwise we'd need to deal with the\npossibility of failure after successful shmem_whiteout().","publishedAt":"2026-01-13T15:31:26.089Z","updatedAt":"2026-10-21T12:38:31.063Z","severity":{"score":8.2,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"8fdbc6f9a994eb327868a4aa74a58953f31a2d0f","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"4b0fe71fb3965d0db83cdfc2f4fe0b3227d70113","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"4642686699a46718d7f2fb5acd1e9d866a9d9cca","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"e1b4c6a58304fd490124cc2b454d80edc786665c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/libfs.c","include/linux/fs.h","mm/shmem.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.6","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.64","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.3","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/libfs.c","include/linux/fs.h","mm/shmem.c"]}],"references":["https://git.kernel.org/stable/c/8fdbc6f9a994eb327868a4aa74a58953f31a2d0f","https://git.kernel.org/stable/c/4b0fe71fb3965d0db83cdfc2f4fe0b3227d70113","https://git.kernel.org/stable/c/4642686699a46718d7f2fb5acd1e9d866a9d9cca","https://git.kernel.org/stable/c/e1b4c6a58304fd490124cc2b454d80edc786665c"],"weaknesses":[],"ingestedAt":"2026-10-29T20:10:04.440Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/71xxx/CVE-2025-71072.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-71072","state":"PUBLISHED","datePublished":"2026-01-13T15:31:26.089Z","dateUpdated":"2026-10-21T12:38:31.063Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:30:19.647Z"},"containers":{"cna":{"title":"shmem: fix recovery on rename failures","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nshmem: fix recovery on rename failures\n\nmaple_tree insertions can fail if we are seriously short on memory;\nsimple_offset_rename() does not recover well if it runs into that.\nThe same goes for simple_offset_rename_exchange().\n\nMoreover, shmem_whiteout() expects that if it succeeds, the caller will\nprogress to d_move(), i.e. that shmem_rename2() won't fail past the\nsuccessful call of shmem_whiteout().\n\nNot hard to fix, fortunately - mtree_store() can't fail if the index we\nare trying to store into is already present in the tree as a singleton.\n\nFor simple_offset_rename_exchange() that's enough - we just need to be\ncareful about the order of operations.\n\nFor simple_offset_rename() solution is to preinsert the target into the\ntree for new_dir; the rest can be done without any potentially failing\noperations.\n\nThat preinsertion has to be done in shmem_rename2() rather than in\nsimple_offset_rename() itself - otherwise we'd need to deal with the\npossibility of failure after successful shmem_whiteout()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"8fdbc6f9a994eb327868a4aa74a58953f31a2d0f","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"4b0fe71fb3965d0db83cdfc2f4fe0b3227d70113","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"4642686699a46718d7f2fb5acd1e9d866a9d9cca","versionType":"git"},{"version":"a2e459555c5f9da3e619b7e47a63f98574dc75f1","status":"affected","lessThan":"e1b4c6a58304fd490124cc2b454d80edc786665c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/libfs.c","include/linux/fs.h","mm/shmem.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.6","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.64","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.3","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/libfs.c","include/linux/fs.h","mm/shmem.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/8fdbc6f9a994eb327868a4aa74a58953f31a2d0f"},{"url":"https://git.kernel.org/stable/c/4b0fe71fb3965d0db83cdfc2f4fe0b3227d70113"},{"url":"https://git.kernel.org/stable/c/4642686699a46718d7f2fb5acd1e9d866a9d9cca"},{"url":"https://git.kernel.org/stable/c/e1b4c6a58304fd490124cc2b454d80edc786665c"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","baseScore":8.2,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - A remote NFS client can invoke ordinary RENAME on a writable tmpfs export through nfsd, reaching shmem_rename2() and the vulnerable offset helpers.\nAC:L - The failure requires severe memory pressure, but an attacker with write access to tmpfs can create files and consume memory while repeatedly attempting renames.\nPR:N - A reasonably configured anonymous writable NFS export can accept AUTH_NULL or mapped AUTH_SYS clients without prior authentication, subject only to directory write and search permissions.\nUI:N - The attacker directly sends rename operations and does not require a victim to perform any action.\nS:U - The corrupted directory state and resulting denial of service remain within the host kernel and filesystem security authority.\nC:N - The failure loses directory-offset mappings but creates no stale freed-object access, out-of-bounds read, or other information-disclosure primitive.\nI:L - A failed insertion can persistently desynchronize a live dentry from its maple-tree mapping, corrupting directory metadata and cookies, but it does not provide arbitrary data modification.\nA:H - The corrupted offsets can make local getdents or NFS READDIR repeat, omit, or fail to progress through entries, potentially rendering the exported directory unavailable to clients."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-21T12:38:31.063Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.12.64"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.18.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.19"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}