{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38652", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:24.030Z", "datePublished": "2025-08-22T16:00:56.445Z", "dateUpdated": "2026-08-05T12:03:40.653Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:03:40.653Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to avoid out-of-boundary access in devs.path\n\n- touch /mnt/f2fs/012345678901234567890123456789012345678901234567890123\n- truncate -s $((1024*1024*1024)) \\\n /mnt/f2fs/012345678901234567890123456789012345678901234567890123\n- touch /mnt/f2fs/file\n- truncate -s $((1024*1024*1024)) /mnt/f2fs/file\n- mkfs.f2fs /mnt/f2fs/012345678901234567890123456789012345678901234567890123 \\\n -c /mnt/f2fs/file\n- mount /mnt/f2fs/012345678901234567890123456789012345678901234567890123 \\\n /mnt/f2fs/loop\n\n[16937.192225] F2FS-fs (loop0): Mount Device [ 0]: /mnt/f2fs/012345678901234567890123456789012345678901234567890123\\xff\\x01, 511, 0 - 3ffff\n[16937.192268] F2FS-fs (loop0): Failed to find devices\n\nIf device path length equals to MAX_PATH_LEN, sbi->devs.path[] may\nnot end up w/ null character due to path array is fully filled, So\naccidently, fields locate after path[] may be treated as part of\ndevice path, result in parsing wrong device path.\n\nstruct f2fs_dev_info {\n...\n\tchar path[MAX_PATH_LEN];\n...\n};\n\nLet's add one byte space for sbi->devs.path[] to store null\ncharacter of device path string." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:H", "baseScore": 7.3, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The only trigger is `mount(2)` of a crafted f2fs image whose superblock `devs[].path` is a full 64 bytes with no terminator (`get_tree_bdev` → `f2fs_fill_super` → `f2fs_scan_devices`), and the resulting disclosure is read back locally via `/proc/fs/f2fs//disk_map`. No network or peer-supplied data reaches this code; between Physical (removable media) and Local, the higher-severity Local applies.\nAC:L - The attacker fully controls the on-disk `f2fs_device.path[64]` bytes and the adjacent `total_segments` value, so filling the path completely deterministically leaves `sbi->devs[i].path` unterminated on every mount — exactly as the reporter demonstrated. There is no race, no memory-layout guessing, and the trailing struct fields (`start_blk`/`end_blk`) are deterministically derived from segment counts the attacker chooses.\nPR:N - The attacker needs no account or privileges on the victim system — only delivery of a malicious f2fs image on an SD card, USB stick, or disk image that a privileged auto-mount daemon (Android vold, udisks2) or administrator later processes, which is the most severe reasonable scenario for f2fs given its role as the standard Android/removable-media filesystem.\nUI:R - f2fs does not set `FS_USERNS_MOUNT`, so mounting requires `CAP_SYS_ADMIN` in the initial user namespace; the crafted image therefore reaches the vulnerable code only when a victim inserts the media or mounts the image, and that mount action constitutes user interaction.\nS:U - The over-read, the leaked slab contents, and any resulting fault all remain within the kernel's own security authority on the host performing the mount; no VM, container, or IOMMU boundary is crossed.\nC:H - The unterminated string is read until an arbitrary in-memory NUL, so the length is determined by heap contents rather than by any bound: the over-read spills into `total_segments`/`start_blk`/`end_blk`, into `nr_blkz` and the `blkz_seq` kernel heap pointer on zoned devices, and past the end of the `kzalloc`'d `f2fs_dev_info` array at its last element. Those bytes are printed verbatim into dmesg and exported through the world-readable 0444 `/proc/fs/f2fs//disk_map`, so adjacent slab data and a kernel heap pointer (defeating KASLR) are disclosed to unprivileged userspace and can be re-read at will.\nI:L - The mis-parsed string is handed to `bdev_file_open_by_path()`, so f2fs can attach to and write filesystem data onto a block device whose path exceeds the 64-byte on-disk field — a target the format otherwise cannot name — corrupting that device's contents. There is no out-of-bounds write or attacker-controlled store, so the modification is limited rather than arbitrary.\nA:H - The strlen/vsnprintf walk past the end of the slab object faults hard on hardened configurations (KFENCE guard page, `panic_on_warn` with a KASAN slab-out-of-bounds report) and can read into unmapped memory at a slab-page boundary, oopsing the mounting task. Even without a fault, the mis-parsed device path aborts the mount with \"Failed to find devices\", leaving the volume — typically the device's primary Android/SD-card storage — unusable." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/f2fs/f2fs.h" ], "versions": [ { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "dc0172c74bd9edaee7bea2ebb35f3dbd37a8ae80", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "1cf1ff15f262e8baf12201b270b6a79f9d119b2d", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "666b7cf6ac9aa074b8319a2b68cba7f2c30023f0", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "3466721f06edff834f99d9f49f23eabc6b2cb78e", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "345fc8d1838f3f8be7c8ed08d86a13dedef67136", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "70849d33130a2cf1d6010069ed200669c8651fbd", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "755427093e4294ac111c3f9e40d53f681a0fbdaa", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "1b1efa5f0e878745e94a98022e8edc675a87d78e", "status": "affected", "versionType": "git" }, { "version": "3c62be17d4f562f43fe1d03b48194399caa35aa5", "lessThan": "5661998536af52848cc4d52a377e90368196edea", "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/f2fs/f2fs.h" ], "versions": [ { "version": "4.10", "status": "affected" }, { "version": "0", "lessThan": "4.10", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.297", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.241", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.190", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.148", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.102", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.42", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.10", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16.1", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17", "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": "4.10", "versionEndExcluding": "5.4.297" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "5.10.241" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "5.15.190" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.1.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.6.102" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.12.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.15.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.16.1" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "6.17" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/dc0172c74bd9edaee7bea2ebb35f3dbd37a8ae80" }, { "url": "https://git.kernel.org/stable/c/1cf1ff15f262e8baf12201b270b6a79f9d119b2d" }, { "url": "https://git.kernel.org/stable/c/666b7cf6ac9aa074b8319a2b68cba7f2c30023f0" }, { "url": "https://git.kernel.org/stable/c/3466721f06edff834f99d9f49f23eabc6b2cb78e" }, { "url": "https://git.kernel.org/stable/c/345fc8d1838f3f8be7c8ed08d86a13dedef67136" }, { "url": "https://git.kernel.org/stable/c/70849d33130a2cf1d6010069ed200669c8651fbd" }, { "url": "https://git.kernel.org/stable/c/755427093e4294ac111c3f9e40d53f681a0fbdaa" }, { "url": "https://git.kernel.org/stable/c/1b1efa5f0e878745e94a98022e8edc675a87d78e" }, { "url": "https://git.kernel.org/stable/c/5661998536af52848cc4d52a377e90368196edea" } ], "title": "f2fs: fix to avoid out-of-boundary access in devs.path", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:40:45.643Z" } } ] } }