Linux: Out-of-bounds Read
CVE-2025-22121 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 27202452b0bc942fdc3db72a44c4dcdab96d5b56, b374e9ecc92aaa7fb2ab221ee3ff5451118ab566, c000a8a9b5343a5ef867df173c6349672dacbd0f as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 27202452b0bc942fdc3db72a44c4dcdab96d5b56 or b374e9ecc92aaa7fb2ab221ee3ff5451118ab566 or c000a8a9b5343a5ef867df173c6349672dacbd0f or 3c591353956ffcace2cc74d09930774afed60619, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.14.2 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, 27202452b0bc942fdc3db72a44c4dcdab96d5b56; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, b374e9ecc92aaa7fb2ab221ee3ff5451118ab566; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, c000a8a9b5343a5ef867df173c6349672dacbd0f; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, 3c591353956ffcace2cc74d09930774afed60619; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, 098927a13fd918bd7c64c2de905350a1ad7b4a3a; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, 0c8fbb6ffb3c8f5164572ca88e4ccb6cd6a41ca8; e50e5129f384ae282adebfb561189cdb19b81cee up to, but not including, 5701875f9609b000d91351eaa6bfd97fe2f157f4; 4.13 | 27202452b0bc942fdc3db72a44c4dcdab96d5b56, b374e9ecc92aaa7fb2ab221ee3ff5451118ab566, c000a8a9b5343a5ef867df173c6349672dacbd0f, 3c591353956ffcace2cc74d09930774afed60619, 098927a13fd918bd7c64c2de905350a1ad7b4a3a, 0c8fbb6ffb3c8f5164572ca88e4ccb6cd6a41ca8 |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) | V3.1.6 and later; V3.1.7 and later | Not stated |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) | V3.1.6 and later; V3.1.7 and later | Not stated |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) | V3.1.6 and later; V3.1.7 and later | Not stated |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) | V3.1.6 and later; V3.1.7 and later | Not stated |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) | V3.1.6 and later; V3.1.7 and later | Not stated |
| Linux | Linux Kernel | 4.13 up to, but not including, 6.14.2 | 6.14.2 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.4 | High | CNA |
| CVSS 3.1 | 7.1 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix out-of-bound read in ext4_xattr_inode_dec_ref_all() There's issue as follows: BUG: KASAN: use-after-free in ext4_xattr_inode_dec_ref_all+0x6ff/0x790 Read of size 4 at addr ffff88807b003000 by task syz-executor.0/15172 CPU: 3 PID: 15172 Comm: syz-executor.0 Call Trace: __dump_stack lib/dump_stack.c:82 [inline] dump_stack+0xbe/0xfd lib/dump_stack.c:123 print_address_description.constprop.0+0x1e/0x280 mm/kasan/report.c:400 __kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560 kasan_report+0x3a/0x50 mm/kasan/report.c:585 ext4_xattr_inode_dec_ref_all+0x6ff/0x790 fs/ext4/xattr.c:1137 ext4_xattr_delete_inode+0x4c7/0xda0 fs/ext4/xattr.c:2896 ext4_evict_inode+0xb3b/0x1670 fs/ext4/inode.c:323 evict+0x39f/0x880 fs/inode.c:622 iput_final fs/inode.c:1746 [inline] iput fs/inode.c:1772 [inline] iput+0x525/0x6c0 fs/inode.c:1758 ext4_orphan_cleanup fs/ext4/super.c:3298 [inline] ext4_fill_super+0x8c57/0xba40 fs/ext4/super.c:5300 mount_bdev+0x355/0x410 fs/super.c:1446 legacy_get_tree+0xfe/0x220 fs/fs_context.c:611 vfs_get_tree+0x8d/0x2f0 fs/super.c:1576 do_new_mount fs/namespace.c:2983 [inline] path_mount+0x119a/0x1ad0 fs/namespace.c:3316 do_mount+0xfc/0x110 fs/namespace.c:3329 __do_sys_mount fs/namespace.c:3540 [inline] __se_sys_mount+0x219/0x2e0 fs/namespace.c:3514 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Memory state around the buggy address: ffff88807b002f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807b002f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88807b003000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88807b003080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88807b003100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff Above issue happens as ext4_xattr_delete_inode() isn't check xattr is valid if xattr is in inode. To solve above issue call xattr_check_inode() check if xattr if valid in inode. In fact, we can directly verify in ext4_iget_extra_inode(), so that there is no divergent verification.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
- git.kernel.org/stable/c/098927a13fd918bd7c64c2de905350a1ad7b4a3a
- git.kernel.org/stable/c/27202452b0bc942fdc3db72a44c4dcdab96d5b56
- git.kernel.org/stable/c/3c591353956ffcace2cc74d09930774afed60619
- git.kernel.org/stable/c/b374e9ecc92aaa7fb2ab221ee3ff5451118ab566
- git.kernel.org/stable/c/c000a8a9b5343a5ef867df173c6349672dacbd0f
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
Recent Out-of-bounds Read vulnerabilities
- 8.8 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
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