{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-50247","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-10-21T19:36:19.978Z","datePublished":"2024-11-09T10:14:56.165Z","dateUpdated":"2026-08-05T11:42:44.376Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:42:44.376Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: Check if more than chunk-size bytes are written\n\nA incorrectly formatted chunk may decompress into\nmore than LZNT_CHUNK_SIZE bytes and a index out of bounds\nwill occur in s_max_off."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H","baseScore":7.3,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The malformed LZNT chunk is delivered on a locally attached or loop-backed NTFS block device and is consumed through ordinary local file I/O (`read`/`mmap` → `ntfs_read_folio` → `ni_readpage_cmpr` → `ni_read_frame` → `decompress_lznt`); no network protocol or remote peer feeds `decompress_chunk()`.\nAC:L - The attacker authors every byte of the compressed chunk, and I confirmed by emulating the loop that an 8-byte chunk (header plus `02 41 FF 0F 42 43`) deterministically emits 4101 bytes and drives `index` past the end of `s_max_off[]`; there is no race, no memory-layout precondition, and the trigger repeats at will.\nPR:L - ntfs3 registers with `FS_REQUIRES_DEV` and no `FS_USERNS_MOUNT`, but udisks2 loop-setup and removable-media automount hand the mount to any active local session on desktop, kiosk, NAS and media-appliance deployments, and ntfs3 mounts default to permissive uid/gid/fmask/dmask. Once mounted, an unprivileged user reaches `decompress_lznt()` by simply reading a compressed file, with no capability check on the path.\nUI:N - The attacker supplies the crafted image, gets it mounted via automount/udisks2, and then performs the triggering `read()`/`mmap()` of the compressed file itself; no action by any other user or administrator is required.\nS:U - The out-of-bounds read, the corrupted decompression state, and any resulting fault all occur inside the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The scan reads kernel memory past the 9-entry global `s_max_off[]` with an attacker-chosen stop threshold (`up - unc`, selectable across [4097, 65535]), so the read is unbounded rather than limited to a few bytes. The resulting `index` feeds `parse_pair()` and therefore changes the `offset`/`length` of the bytes materialized into the frame the attacker reads back, turning the out-of-bounds contents into a binary-search oracle over post-array kernel memory — which in ntfs3's module `.rodata` includes relocated pointers, leaking the KASLR base.\nI:L - I traced every store: `offset` is rejected by `if (unc + offset > up) return -EINVAL;` and `length` is truncated by `if (up + length >= unc_end) length = unc_end - up;`, so even with the UB shifts in `parse_pair()` at `index > 12` no write escapes the frame buffer — there is no memory-corruption or control-flow primitive here. The bounded integrity effect is that the corrupted `index` makes the kernel materialize wrong bytes into the compressed file's page cache, which the RMW path at `fs/ntfs3/file.c:1039`/`:1104` recompresses and writes back, persisting bad content on a volume other users of that shared media then read.\nA:H - The index-correction loop has no upper bound and keeps advancing until it finds an out-of-bounds qword at least as large as the attacker-selected threshold, so on the common `CONFIG_NTFS3_FS=m` builds it can run past the module's read-only region into a vmalloc guard page and take a kernel page fault — an oops, and a full panic on the many embedded and hardened deployments running `panic_on_oops`. On KASAN builds the very first access at `index == 9` is an immediate global-out-of-bounds BUG, which is precisely the syzbot-reported crash class that motivated the later `a93980141253` hardening."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/lznt.c"],"versions":[{"version":"4534a70b7056fd4b9a1c6db5a4ce3c98546b291e","lessThan":"e5ae7859008688626b4d2fa6139eeaa08e255053","status":"affected","versionType":"git"},{"version":"4534a70b7056fd4b9a1c6db5a4ce3c98546b291e","lessThan":"1b6bc5f7212181093b6c5310eea216fc09c721a9","status":"affected","versionType":"git"},{"version":"4534a70b7056fd4b9a1c6db5a4ce3c98546b291e","lessThan":"5f21e3e60982cd7353998b4f59f052134fd47d64","status":"affected","versionType":"git"},{"version":"4534a70b7056fd4b9a1c6db5a4ce3c98546b291e","lessThan":"4a4727bc582832f354e0d3d49838a401a28ae25e","status":"affected","versionType":"git"},{"version":"4534a70b7056fd4b9a1c6db5a4ce3c98546b291e","lessThan":"9931122d04c6d431b2c11b5bb7b10f28584067f0","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/lznt.c"],"versions":[{"version":"5.15","status":"affected"},{"version":"0","lessThan":"5.15","status":"unaffected","versionType":"semver"},{"version":"5.15.171","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.116","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.60","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.11.7","lessThanOrEqual":"6.11.*","status":"unaffected","versionType":"semver"},{"version":"6.12","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":"5.15.171"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.116"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.60"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.11.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/e5ae7859008688626b4d2fa6139eeaa08e255053"},{"url":"https://git.kernel.org/stable/c/1b6bc5f7212181093b6c5310eea216fc09c721a9"},{"url":"https://git.kernel.org/stable/c/5f21e3e60982cd7353998b4f59f052134fd47d64"},{"url":"https://git.kernel.org/stable/c/4a4727bc582832f354e0d3d49838a401a28ae25e"},{"url":"https://git.kernel.org/stable/c/9931122d04c6d431b2c11b5bb7b10f28584067f0"}],"title":"fs/ntfs3: Check if more than chunk-size bytes are written","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.1,"attackVector":"LOCAL","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2024-50247","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T20:15:58.403606Z"}}}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","cweId":"CWE-125","description":"CWE-125 Out-of-bounds Read"}]}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2025-10-01T20:17:25.362Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T22:27:27.327Z"}}]}}