{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-37738", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.935Z", "datePublished": "2025-05-01T12:55:47.981Z", "dateUpdated": "2026-08-05T11:57:11.635Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:57:11.635Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: ignore xattrs past end\n\nOnce inside 'ext4_xattr_inode_dec_ref_all' we should\nignore xattrs entries past the 'end' entry.\n\nThis fixes the following KASAN reported issue:\n\n==================================================================\nBUG: KASAN: slab-use-after-free in ext4_xattr_inode_dec_ref_all+0xb8c/0xe90\nRead of size 4 at addr ffff888012c120c4 by task repro/2065\n\nCPU: 1 UID: 0 PID: 2065 Comm: repro Not tainted 6.13.0-rc2+ #11\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\nCall Trace:\n \n dump_stack_lvl+0x1fd/0x300\n ? tcp_gro_dev_warn+0x260/0x260\n ? _printk+0xc0/0x100\n ? read_lock_is_recursive+0x10/0x10\n ? irq_work_queue+0x72/0xf0\n ? __virt_addr_valid+0x17b/0x4b0\n print_address_description+0x78/0x390\n print_report+0x107/0x1f0\n ? __virt_addr_valid+0x17b/0x4b0\n ? __virt_addr_valid+0x3ff/0x4b0\n ? __phys_addr+0xb5/0x160\n ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90\n kasan_report+0xcc/0x100\n ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90\n ext4_xattr_inode_dec_ref_all+0xb8c/0xe90\n ? ext4_xattr_delete_inode+0xd30/0xd30\n ? __ext4_journal_ensure_credits+0x5f0/0x5f0\n ? __ext4_journal_ensure_credits+0x2b/0x5f0\n ? inode_update_timestamps+0x410/0x410\n ext4_xattr_delete_inode+0xb64/0xd30\n ? ext4_truncate+0xb70/0xdc0\n ? ext4_expand_extra_isize_ea+0x1d20/0x1d20\n ? __ext4_mark_inode_dirty+0x670/0x670\n ? ext4_journal_check_start+0x16f/0x240\n ? ext4_inode_is_fast_symlink+0x2f2/0x3a0\n ext4_evict_inode+0xc8c/0xff0\n ? ext4_inode_is_fast_symlink+0x3a0/0x3a0\n ? do_raw_spin_unlock+0x53/0x8a0\n ? ext4_inode_is_fast_symlink+0x3a0/0x3a0\n evict+0x4ac/0x950\n ? proc_nr_inodes+0x310/0x310\n ? trace_ext4_drop_inode+0xa2/0x220\n ? _raw_spin_unlock+0x1a/0x30\n ? iput+0x4cb/0x7e0\n do_unlinkat+0x495/0x7c0\n ? try_break_deleg+0x120/0x120\n ? 0xffffffff81000000\n ? __check_object_size+0x15a/0x210\n ? strncpy_from_user+0x13e/0x250\n ? getname_flags+0x1dc/0x530\n __x64_sys_unlinkat+0xc8/0xf0\n do_syscall_64+0x65/0x110\n entry_SYSCALL_64_after_hwframe+0x67/0x6f\nRIP: 0033:0x434ffd\nCode: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 8\nRSP: 002b:00007ffc50fa7b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000107\nRAX: ffffffffffffffda RBX: 00007ffc50fa7e18 RCX: 0000000000434ffd\nRDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005\nRBP: 00007ffc50fa7be0 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001\nR13: 00007ffc50fa7e08 R14: 00000000004bbf30 R15: 0000000000000001\n \n\nThe buggy address belongs to the object at ffff888012c12000\n which belongs to the cache filp of size 360\nThe buggy address is located 196 bytes inside of\n freed 360-byte region [ffff888012c12000, ffff888012c12168)\n\nThe buggy address belongs to the physical page:\npage: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12c12\nhead: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0\nflags: 0x40(head|node=0|zone=0)\npage_type: f5(slab)\nraw: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004\nraw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000\nhead: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004\nhead: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000\nhead: 0000000000000001 ffffea00004b0481 ffffffffffffffff 0000000000000000\nhead: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000\npage dumped because: kasan: bad access detected\n\nMemory state around the buggy address:\n ffff888012c11f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\n ffff888012c12000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n> ffff888012c12080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n ^\n ffff888012c12100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc\n ffff888012c12180: fc fc fc fc fc fc fc fc fc\n---truncated---" } ], "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 vulnerability is triggered by mounting a crafted ext4 image and then performing an ordinary `unlinkat()` on it, i.e. entirely through local syscalls against a locally attached filesystem. There is no network-facing path into ext4 xattr eviction.\nAC:L - The attacker fully controls the on-disk inode/xattr-block bytes and the moment of inode eviction, so the out-of-bounds walk is deterministic — syzkaller has a reproducer. Nothing required is outside the attacker's control; heap layout for weaponization is groomable via ordinary file/slab allocations.\nPR:L - In the realistic worst case an unprivileged local user reaches this on the many deployments where removable media is auto-mounted on their behalf (udisks2/systemd on desktops, autofs, Android vold on portable storage, kiosk and shared-workstation builds), after which the triggering `unlink()` needs no privilege at all. Even where a mount capability is nominally required, the attacker-facing half of the path is fully unprivileged.\nUI:N - In the kiosk, shared-workstation and automount scenarios the attacker supplies the medium and issues the `unlink()` themselves, with no victim action required. Where any interaction is arguable it is only the mount, so the higher-severity value applies.\nS:U - The corruption is confined to kernel memory and kernel-managed filesystem state within the same security authority; no hypervisor, IOMMU or sandbox boundary is crossed.\nC:H - The unbounded walk reads adjacent and freed slab objects — KASAN confirms a use-after-free read inside a freed `struct file` — and those values are consumed as inode numbers, while the resulting UAF/heap corruption is leverageable for broader disclosure. Decrementing refs on arbitrary inode numbers can additionally expose unrelated files' contents.\nI:H - Beyond the OOB read, the loop performs an out-of-bounds 8-byte zero write (`e_value_inum`/`e_value_size`) into neighbouring slab memory and calls `ext4_xattr_inode_dec_ref()` on attacker-influenced inodes, freeing and orphan-listing arbitrary inodes. A controlled zeroing primitive in the `filp`-sized slab is a classic route to control-flow hijack and privilege escalation.\nA:H - The confirmed slab-use-after-free readily oopses the kernel, and the unbounded stride can walk into unmapped memory or corrupt live objects, while erroneous inode ref-decrements corrupt on-disk filesystem state. Any of these yields a kernel panic or unusable filesystem." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ext4/xattr.c" ], "versions": [ { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "6aff941cb0f7d0c897c3698ad2e30672709135e3", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "f737418b6de31c962c7192777ee4018906975383", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "cf9291a3449b04688b81e32621e88de8f4314b54", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "362a90cecd36e8a5c415966d0b75b04a0270e4dd", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "eb59cc31b6ea076021d14b04e7faab1636b87d0e", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "3bc6317033f365ce578eb6039445fb66162722fd", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "836e625b03a666cf93ff5be328c8cb30336db872", "status": "affected", "versionType": "git" }, { "version": "e50e5129f384ae282adebfb561189cdb19b81cee", "lessThan": "c8e008b60492cf6fd31ef127aea6d02fd3d314cd", "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/xattr.c" ], "versions": [ { "version": "4.13", "status": "affected" }, { "version": "0", "lessThan": "4.13", "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": "4.13", "versionEndExcluding": "5.4.293" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.10.237" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.15.181" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.1.135" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.6.88" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.12.24" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.13.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.14.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6aff941cb0f7d0c897c3698ad2e30672709135e3" }, { "url": "https://git.kernel.org/stable/c/76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3" }, { "url": "https://git.kernel.org/stable/c/f737418b6de31c962c7192777ee4018906975383" }, { "url": "https://git.kernel.org/stable/c/cf9291a3449b04688b81e32621e88de8f4314b54" }, { "url": "https://git.kernel.org/stable/c/362a90cecd36e8a5c415966d0b75b04a0270e4dd" }, { "url": "https://git.kernel.org/stable/c/eb59cc31b6ea076021d14b04e7faab1636b87d0e" }, { "url": "https://git.kernel.org/stable/c/3bc6317033f365ce578eb6039445fb66162722fd" }, { "url": "https://git.kernel.org/stable/c/836e625b03a666cf93ff5be328c8cb30336db872" }, { "url": "https://git.kernel.org/stable/c/c8e008b60492cf6fd31ef127aea6d02fd3d314cd" } ], "title": "ext4: ignore xattrs past end", "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": "2025-11-03T19:54:10.977Z" } } ] } }