{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-23150","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-01-11T14:28:41.513Z","datePublished":"2025-05-01T12:55:38.190Z","dateUpdated":"2026-08-05T11:57:03.997Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:57:03.997Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix off-by-one error in do_split\n\nSyzkaller detected a use-after-free issue in ext4_insert_dentry that was\ncaused by out-of-bounds access due to incorrect splitting in do_split.\n\nBUG: KASAN: use-after-free in ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2109\nWrite of size 251 at addr ffff888074572f14 by task syz-executor335/5847\n\nCPU: 0 UID: 0 PID: 5847 Comm: syz-executor335 Not tainted 6.12.0-rc6-syzkaller-00318-ga9cda7c0ffed #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:377 [inline]\n print_report+0x169/0x550 mm/kasan/report.c:488\n kasan_report+0x143/0x180 mm/kasan/report.c:601\n kasan_check_range+0x282/0x290 mm/kasan/generic.c:189\n __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106\n ext4_insert_dentry+0x36a/0x6d0 fs/ext4/namei.c:2109\n add_dirent_to_buf+0x3d9/0x750 fs/ext4/namei.c:2154\n make_indexed_dir+0xf98/0x1600 fs/ext4/namei.c:2351\n ext4_add_entry+0x222a/0x25d0 fs/ext4/namei.c:2455\n ext4_add_nondir+0x8d/0x290 fs/ext4/namei.c:2796\n ext4_symlink+0x920/0xb50 fs/ext4/namei.c:3431\n vfs_symlink+0x137/0x2e0 fs/namei.c:4615\n do_symlinkat+0x222/0x3a0 fs/namei.c:4641\n __do_sys_symlink fs/namei.c:4662 [inline]\n __se_sys_symlink fs/namei.c:4660 [inline]\n __x64_sys_symlink+0x7a/0x90 fs/namei.c:4660\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n </TASK>\n\nThe following loop is located right above 'if' statement.\n\nfor (i = count-1; i >= 0; i--) {\n\t/* is more than half of this entry in 2nd half of the block? */\n\tif (size + map[i].size/2 > blocksize/2)\n\t\tbreak;\n\tsize += map[i].size;\n\tmove++;\n}\n\n'i' in this case could go down to -1, in which case sum of active entries\nwouldn't exceed half the block size, but previous behaviour would also do\nsplit in half if sum would exceed at the very last block, which in case of\nhaving too many long name files in a single block could lead to\nout-of-bounds access and following use-after-free.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller."}],"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 vulnerable path is reached purely through local filesystem syscalls (symlink, open(O_CREAT), mkdir, link, mknod, rename) via ext4_add_entry() on a locally mounted ext4 filesystem. No network protocol handling is involved.\nAC:L - The attacker fully controls every filename in the target directory, and therefore every dirent size, every hash, the sorted map ordering, the loop break index, and which split block receives the new entry; favorable layouts are cheaply brute-forced in fresh directories. The 1024-byte block size required is the mke2fs default for filesystems under 512 MB (embedded/IoT rootfs, SD cards, USB media, /boot, small images) and is directly attacker-chosen when the attacker supplies the medium.\nPR:L - Only an ordinary unprivileged local user is needed — write permission on any directory of the affected ext4 filesystem (e.g. /tmp, a home directory, or a mounted removable volume). No capabilities, no user namespace tricks, and no root are required.\nUI:N - The attacker performs all the file-creation operations themselves; no crafted or corrupted filesystem image needs to be mounted and no victim action of any kind is required.\nS:U - The out-of-bounds write corrupts kernel heap/page-cache memory within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The overflow writes attacker-controlled bytes into memory adjacent to the directory block, allowing forged ext4_dir_entry_2 records with attacker-chosen inode numbers that grant read access to arbitrary inodes on the filesystem regardless of permissions, and the resulting heap corruption is leverageable into an arbitrary-read primitive (KASAN reports it as a use-after-free).\nI:H - This is a linear heap out-of-bounds write of up to ~263 bytes whose contents are entirely attacker-supplied (the filename), landing either in adjacent page-cache directory data or past the folio into arbitrary kernel memory — a classic controlled-overflow primitive for arbitrary write and control-flow hijack, plus direct on-disk filesystem corruption.\nA:H - The bug is a KASAN-confirmed out-of-bounds/use-after-free write that reliably produces kernel oops/panic and persistent directory corruption requiring fsck, and it can be re-triggered at will by an unprivileged user."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/namei.c"],"versions":[{"version":"ea54176e5821936d109bb45dc2c19bd53559e735","lessThan":"b96bd2c3db26ad0daec5b78c85c098b53900e2e1","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"515c34cff899eb5dae6aa7eee01c1295b07d81af","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"2883e9e74f73f9265e5f8d1aaaa89034b308e433","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"35d0aa6db9d93307085871ceab8a729594a98162","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"2eeb1085bf7bd5c7ba796ca4119925fa5d336a3f","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"16d9067f00e3a7d1df7c3aa9c20d214923d27e10","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"17df39f455f1289319d4d09e4826aa46852ffd17","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"ab0cc5c25552ae0d20eae94b40a93be11b080fc5","status":"affected","versionType":"git"},{"version":"5872331b3d91820e14716632ebb56b1399b34fe1","lessThan":"94824ac9a8aaf2fb3c54b4bdde842db80ffa555d","status":"affected","versionType":"git"},{"version":"059b1480105478c5f68cf664301545b8cad6a7cf","status":"affected","versionType":"git"},{"version":"539ae3e03875dacaa9c388aff141ccbb4ef4ecb5","status":"affected","versionType":"git"},{"version":"fbbfd55a40d5d0806b59ee0403c75d5ac517533f","status":"affected","versionType":"git"},{"version":"b3ddf6ba5e28a57729fff1605ae08e21be5c92e3","status":"affected","versionType":"git"},{"version":"e50fe43e3062e18846e99d9646b9c07b097eb1ed","status":"affected","versionType":"git"},{"version":"88e79f7a9841278fa8ff7ff6178bad12da002ffc","status":"affected","versionType":"git"},{"version":"5.4.61","lessThan":"5.4.293","status":"affected","versionType":"semver"},{"version":"4.4.234","lessThan":"4.5","status":"affected","versionType":"semver"},{"version":"4.9.234","lessThan":"4.10","status":"affected","versionType":"semver"},{"version":"4.14.195","lessThan":"4.15","status":"affected","versionType":"semver"},{"version":"4.19.142","lessThan":"4.20","status":"affected","versionType":"semver"},{"version":"5.7.18","lessThan":"5.8","status":"affected","versionType":"semver"},{"version":"5.8.4","lessThan":"5.9","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/namei.c"],"versions":[{"version":"5.9","status":"affected"},{"version":"0","lessThan":"5.9","status":"unaffected","versionType":"semver"},{"version":"5.4.293","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.237","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.181","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.135","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.88","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.24","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.13.12","lessThanOrEqual":"6.13.*","status":"unaffected","versionType":"semver"},{"version":"6.14.3","lessThanOrEqual":"6.14.*","status":"unaffected","versionType":"semver"},{"version":"6.15","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":"5.4.61","versionEndExcluding":"5.4.293"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.10.237"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.15.181"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.1.135"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.6.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.12.24"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.13.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionS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fix off-by-one error in do_split","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T19:42:46.918Z"}},{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2025-23150","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-06-10T20:41:10.502771Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-11T18:44:09.529Z"}}]}}