{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31716","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.133Z","datePublished":"2026-05-01T13:56:11.263Z","dateUpdated":"2026-08-05T12:24:47.538Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:24:47.538Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: validate rec->used in journal-replay file record check\n\ncheck_file_record() validates rec->total against the record size but\nnever validates rec->used.  The do_action() journal-replay handlers read\nrec->used from disk and use it to compute memmove lengths:\n\n  DeleteAttribute:    memmove(attr, ..., used - asize - roff)\n  CreateAttribute:    memmove(..., attr, used - roff)\n  change_attr_size:   memmove(..., used - PtrOffset(rec, next))\n\nWhen rec->used is smaller than the offset of a validated attribute, or\nlarger than the record size, these subtractions can underflow allowing\nus to copy huge amounts of memory in to a 4kb buffer, generally\nconsidered a bad idea overall.\n\nThis requires a corrupted filesystem, which isn't a threat model the\nkernel really needs to worry about, but checking for such an obvious\nout-of-bounds value is good to keep things robust, especially on journal\nreplay\n\nFix this up by bounding rec->used correctly.\n\nThis is much like commit b2bc7c44ed17 (\"fs/ntfs3: Fix slab-out-of-bounds\nread in DeleteIndexEntryRoot\") which checked different values in this\nsame switch statement."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable ntfs3 journal replay code is reached when the target mounts or otherwise processes a crafted NTFS block device/image, which is a local filesystem parsing path rather than a network protocol. Physical removable media is one delivery route, but local image/block-device mounting is also reasonable.\nAC:L - The attacker controls the corrupt NTFS metadata and journal records, including the `rec->used` value and replay operation needed to trigger the underflowed `memmove()` length. No race or external timing condition is required.\nPR:N - Direct self-triggered mounting is gated by `CAP_SYS_ADMIN` and ntfs3 is not user-namespace mountable, but the highest reasonable scenario is an attacker-supplied NTFS image/media mounted by a victim or automounter. In that scenario the attacker needs no privileges on the target.\nUI:R - Exploitation requires the target system or user to mount/process the crafted NTFS filesystem so journal replay runs. The attacker cannot reach this ntfs3 path solely by sending packets.\nS:U - The impact remains within the same kernel security authority. This is not a VM escape, IOMMU bypass, or cross-scope boundary violation.\nC:H - The bug creates out-of-bounds memory movement from attacker-controlled on-disk metadata into a small MFT record buffer, and the resulting kernel memory corruption/read exposure is not tightly bounded. When uncertain, the higher impact is appropriate.\nI:H - The underflowed `memmove()` length can overflow/corrupt kernel heap memory adjacent to the MFT record buffer. Such out-of-bounds write-style memory corruption is potentially exploitable for arbitrary modification or code execution.\nA:H - The same oversized `memmove()` can cause kernel heap corruption, faults, oopses, or panics during mount-time journal replay. This is a high availability impact."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/fslog.c"],"versions":[{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"8e64d33198b5a0fb14a452708bad844f94f03b2c","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"1393a467a9607e62123806de7d4c3a3e54e396a9","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"f90b8a1798b750755a9e9aee66678f0a1820bbaf","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"4b1613d7e2deda831a97e427d1ea586e50fe1be5","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"0112e6279420d4005b3d57af36fb45c01b8d0116","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"f79d0403ea20a81bc29105bba54fbcab54e8c403","status":"affected","versionType":"git"},{"version":"b46acd6a6a627d876898e1c84d3f84902264b445","lessThan":"0ca0485e4b2e837ebb6cbd4f2451aba665a03e4b","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/fslog.c"],"versions":[{"version":"5.15","status":"affected"},{"version":"0","lessThan":"5.15","status":"unaffected","versionType":"semver"},{"version":"5.15.209","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.175","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.136","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.84","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.25","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.2","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","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":"5.15","versionEndExcluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.136"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12.84"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.18.25"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.0.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/8e64d33198b5a0fb14a452708bad844f94f03b2c"},{"url":"https://git.kernel.org/stable/c/1393a467a9607e62123806de7d4c3a3e54e396a9"},{"url":"https://git.kernel.org/stable/c/f90b8a1798b750755a9e9aee66678f0a1820bbaf"},{"url":"https://git.kernel.org/stable/c/4b1613d7e2deda831a97e427d1ea586e50fe1be5"},{"url":"https://git.kernel.org/stable/c/0112e6279420d4005b3d57af36fb45c01b8d0116"},{"url":"https://git.kernel.org/stable/c/f79d0403ea20a81bc29105bba54fbcab54e8c403"},{"url":"https://git.kernel.org/stable/c/0ca0485e4b2e837ebb6cbd4f2451aba665a03e4b"}],"title":"fs/ntfs3: validate rec->used in journal-replay file record check","x_generator":{"engine":"bippy-1.2.0"}}}}