{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-37785", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.940Z", "datePublished": "2025-04-18T07:01:27.393Z", "dateUpdated": "2026-08-05T11:57:31.764Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:57:31.764Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix OOB read when checking dotdot dir\n\nMounting a corrupted filesystem with directory which contains '.' dir\nentry with rec_len == block size results in out-of-bounds read (later\non, when the corrupted directory is removed).\n\next4_empty_dir() assumes every ext4 directory contains at least '.'\nand '..' as directory entries in the first data block. It first loads\nthe '.' dir entry, performs sanity checks by calling ext4_check_dir_entry()\nand then uses its rec_len member to compute the location of '..' dir\nentry (in ext4_next_entry). It assumes the '..' dir entry fits into the\nsame data block.\n\nIf the rec_len of '.' is precisely one block (4KB), it slips through the\nsanity checks (it is considered the last directory entry in the data\nblock) and leaves \"struct ext4_dir_entry_2 *de\" point exactly past the\nmemory slot allocated to the data block. The following call to\next4_check_dir_entry() on new value of de then dereferences this pointer\nwhich results in out-of-bounds mem access.\n\nFix this by extending __ext4_check_dir_entry() to check for '.' dir\nentries that reach the end of data block. Make sure to ignore the phony\ndir entries for checksum (by checking name_len for non-zero).\n\nNote: This is reported by KASAN as use-after-free in case another\nstructure was recently freed from the slot past the bound, but it is\nreally an OOB read.\n\nThis issue was found by syzkaller tool.\n\nCall Trace:\n[ 38.594108] BUG: KASAN: slab-use-after-free in __ext4_check_dir_entry+0x67e/0x710\n[ 38.594649] Read of size 2 at addr ffff88802b41a004 by task syz-executor/5375\n[ 38.595158]\n[ 38.595288] CPU: 0 UID: 0 PID: 5375 Comm: syz-executor Not tainted 6.14.0-rc7 #1\n[ 38.595298] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\n[ 38.595304] Call Trace:\n[ 38.595308] \n[ 38.595311] dump_stack_lvl+0xa7/0xd0\n[ 38.595325] print_address_description.constprop.0+0x2c/0x3f0\n[ 38.595339] ? __ext4_check_dir_entry+0x67e/0x710\n[ 38.595349] print_report+0xaa/0x250\n[ 38.595359] ? __ext4_check_dir_entry+0x67e/0x710\n[ 38.595368] ? kasan_addr_to_slab+0x9/0x90\n[ 38.595378] kasan_report+0xab/0xe0\n[ 38.595389] ? __ext4_check_dir_entry+0x67e/0x710\n[ 38.595400] __ext4_check_dir_entry+0x67e/0x710\n[ 38.595410] ext4_empty_dir+0x465/0x990\n[ 38.595421] ? __pfx_ext4_empty_dir+0x10/0x10\n[ 38.595432] ext4_rmdir.part.0+0x29a/0xd10\n[ 38.595441] ? __dquot_initialize+0x2a7/0xbf0\n[ 38.595455] ? __pfx_ext4_rmdir.part.0+0x10/0x10\n[ 38.595464] ? __pfx___dquot_initialize+0x10/0x10\n[ 38.595478] ? down_write+0xdb/0x140\n[ 38.595487] ? __pfx_down_write+0x10/0x10\n[ 38.595497] ext4_rmdir+0xee/0x140\n[ 38.595506] vfs_rmdir+0x209/0x670\n[ 38.595517] ? lookup_one_qstr_excl+0x3b/0x190\n[ 38.595529] do_rmdir+0x363/0x3c0\n[ 38.595537] ? __pfx_do_rmdir+0x10/0x10\n[ 38.595544] ? strncpy_from_user+0x1ff/0x2e0\n[ 38.595561] __x64_sys_unlinkat+0xf0/0x130\n[ 38.595570] do_syscall_64+0x5b/0x180\n[ 38.595583] entry_SYSCALL_64_after_hwframe+0x76/0x7e" } ], "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 - Triggering requires a crafted ext4 image to be mounted locally and then an `unlinkat(AT_REMOVEDIR)`/rename syscall against the corrupted directory; there is no network-facing path to `ext4_empty_dir()`. Local attack vector scores higher than physical and correctly models USB/auto-mount and loop-mount delivery.\nAC:L - The condition is fully deterministic and entirely attacker-authored — setting the `.` entry's `rec_len` to exactly the block size in the image reliably slips past every sanity check in `__ext4_check_dir_entry()` and lands `de` past the block on every attempt. No race, timing, or uncontrolled memory-layout requirement.\nPR:L - Once the image is mounted (via udisks2/GNOME auto-mount of removable media on desktops and kiosks, or an fstab `user` entry), any unprivileged local user with ordinary access to the mount can invoke `rmdir` and reach `ext4_empty_dir()`; no capability check gates the path.\nUI:N - In the auto-mount scenario the attacker performs both steps themselves — inserting the media triggers the mount automatically and the same attacker issues the `rmdir` — so no action by a separate user is required.\nS:U - The out-of-bounds access, the disclosure, and the panic all occur within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The read reaches into the adjacent slab object/page and its contents are exfiltrated to userspace-visible dmesg through `ext4_error_inode()`, which prints the out-of-bounds `inode` and `rec_len` fields verbatim. The operation is cheaply repeatable and the neighbouring slot can be heap-groomed, making it a practical kernel heap/pointer disclosure primitive rather than a bounded one-shot leak.\nI:H - Data read out of bounds directly controls subsequent logic — if the adjacent heap bytes decode as a valid `..` entry, `ext4_empty_dir()` wrongly reports the directory empty and `rmdir`/`rename` proceeds to unlink a non-empty directory, and the OOB `rec_len` drives the following offset walk. KASAN classifies the access as a use-after-free on the neighbouring freed object, so attacker-groomed heap state translates into corrupted filesystem-metadata operations.\nA:H - The error path is reached with the attacker-controlled superblock, and `s_errors = EXT4_ERRORS_PANIC` (`fs/ext4/super.c:4364`) makes `ext4_error_inode()` call `panic()` at `super.c:735`, giving a guaranteed kernel panic. Independently, the read past the block can fault on an unmapped or poisoned page, and on debug/KASAN kernels it is an immediate BUG." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ext4/dir.c" ], "versions": [ { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "14da7dbecb430e35b5889da8dae7bef33173b351", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "e47f472a664d70a3d104a6c2a035cdff55a719b4", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "b7531a4f99c3887439d778afaf418d1a01a5f01b", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "89503e5eae64637d0fa2218912b54660effe7d93", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "52a5509ab19a5d3afe301165d9b5787bba34d842", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "b47584c556444cf7acb66b26a62cbc348eb92b78", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "ac28c5684c1cdab650a7e5065b19e91577d37a4b", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "53bc45da8d8da92ec07877f5922b130562eb4b00", "status": "affected", "versionType": "git" }, { "version": "ac27a0ec112a089f1a5102bc8dffc79c8c815571", "lessThan": "d5e206778e96e8667d3bde695ad372c296dc9353", "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/ext4/dir.c" ], "versions": [ { "version": "2.6.19", "status": "affected" }, { "version": "0", "lessThan": "2.6.19", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.293", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.236", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.180", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.134", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.87", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.23", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13.11", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14.2", "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": "2.6.19", "versionEndExcluding": "5.4.293" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "5.10.236" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "5.15.180" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.1.134" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.6.87" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.12.23" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.13.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.14.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.19", "versionEndExcluding": "6.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/14da7dbecb430e35b5889da8dae7bef33173b351" }, { "url": "https://git.kernel.org/stable/c/e47f472a664d70a3d104a6c2a035cdff55a719b4" }, { "url": "https://git.kernel.org/stable/c/b7531a4f99c3887439d778afaf418d1a01a5f01b" }, { "url": "https://git.kernel.org/stable/c/89503e5eae64637d0fa2218912b54660effe7d93" }, { "url": "https://git.kernel.org/stable/c/52a5509ab19a5d3afe301165d9b5787bba34d842" }, { "url": "https://git.kernel.org/stable/c/b47584c556444cf7acb66b26a62cbc348eb92b78" }, { "url": "https://git.kernel.org/stable/c/ac28c5684c1cdab650a7e5065b19e91577d37a4b" }, { "url": "https://git.kernel.org/stable/c/53bc45da8d8da92ec07877f5922b130562eb4b00" }, { "url": "https://git.kernel.org/stable/c/d5e206778e96e8667d3bde695ad372c296dc9353" } ], "title": "ext4: fix OOB read when checking dotdot dir", "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": "2025-11-03T19:55:07.824Z" } }, { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-07-14T12:41:10.094Z" }, "affected": [ { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" } ], "references": [ { "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html" } ] } ] } }