f2fs: validate ACL entry sizes in f2fs_acl_from_disk()

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-63814
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-07-19 12:16:54 UTC
Updated2026-07-20 15:16:48 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: f2fs: validate ACL entry sizes in f2fs_acl_from_disk() f2fs_acl_count() only validates the aggregate ACL xattr length. A malformed ACL can still place ACL_USER or ACL_GROUP in a slot that only contains struct f2fs_acl_entry_short bytes, and f2fs_acl_from_disk() then reads entry->e_id before verifying that a full entry fits. Require a short entry before reading e_tag and e_perm, and require a full entry before reading e_id for ACL_USER and ACL_GROUP. Return -EFSCORRUPTED from these new truncated-entry checks, while keeping the pre-existing -EINVAL paths unchanged. Validation reproduced this kernel report: KASAN slab-out-of-bounds in __f2fs_get_acl+0x6fb/0x7e0 RIP: 0033:0x7f4b835ea7aa The buggy address belongs to the object at ffff888114589960 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes to the right of allocated 8-byte region [ffff888114589960, ffff888114589968) Read of size 4 Call trace: dump_stack_lvl+0x66/0xa0 (?:?) print_report+0xce/0x630 (?:?) __f2fs_get_acl+0x6fb/0x7e0 (fs/f2fs/acl.c:169) srso_alias_return_thunk+0x5/0xfbef5 (?:?) __virt_addr_valid+0x224/0x430 (?:?) kasan_report+0xe0/0x110 (?:?) __f2fs_get_acl+0x5/0x7e0 (fs/f2fs/acl.c:169) __get_acl+0x281/0x380 (?:?) vfs_get_acl+0x10b/0x190 (?:?) do_get_acl+0x2a/0x410 (?:?) do_get_acl+0x9/0x410 (?:?) do_getxattr+0xe8/0x260 (?:?) filename_getxattr+0xd1/0x140 (?:?) do_getname+0x2d/0x2d0 (?:?) path_getxattrat+0x16c/0x200 (?:?) lock_release+0xc8/0x290 (?:?) cgroup_update_frozen+0x9d/0x320 (?:?) lockdep_hardirqs_on_prepare+0xea/0x1a0 (?:?) trace_hardirqs_on+0x1a/0x170 (?:?) _raw_spin_unlock_irq+0x28/0x50 (?:?) do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87) entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?)

Risk And Classification

Primary CVSS: v3.1 7.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.001650000 probability, percentile 0.060310000 (date 2026-07-20)

VersionSourceTypeScoreSeverityVector
3.1416baaa9-dc9f-4396-8d5f-8c081fb06d67Secondary7.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
3.1CNADECLARED7.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da 733cd8474e6d763d75ed96f3f2b98a25480cf2b9 git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da 4e2a96ec7236e248e706850568e0a925fd21b588 git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da 442ca20c54038e2400cf28aaa944cf1de2c8e65d git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da 1ddf3fd21c4c652f9cab5552515c04a166662306 git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da aba4f94ac1832c7299c33e1b4fe5f87eef6dc8f1 git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da ff83de56882cb8466184d322abece2589258ca56 git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da 5d8a39649947a4e86c8fbc682d7fc0041b8d109a git Not specified
CNA Linux Linux affected af48b85b8cd3fbb12c9b6759c16db6d69c0b03da c4810ada31e80cbe4011467c4f3b1e93f94134f3 git Not specified
CNA Linux Linux affected 3.8 Not specified
CNA Linux Linux unaffected 3.8 semver Not specified
CNA Linux Linux unaffected 5.10.260 5.10.* semver Not specified
CNA Linux Linux unaffected 5.15.211 5.15.* semver Not specified
CNA Linux Linux unaffected 6.1.177 6.1.* semver Not specified
CNA Linux Linux unaffected 6.6.144 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.95 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.38 6.18.* semver Not specified
CNA Linux Linux unaffected 7.1.3 7.1.* semver Not specified
CNA Linux Linux unaffected 7.2-rc1 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/ff83de56882cb8466184d322abece2589258ca56 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/5d8a39649947a4e86c8fbc682d7fc0041b8d109a 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/442ca20c54038e2400cf28aaa944cf1de2c8e65d 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/4e2a96ec7236e248e706850568e0a925fd21b588 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/c4810ada31e80cbe4011467c4f3b1e93f94134f3 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/1ddf3fd21c4c652f9cab5552515c04a166662306 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/733cd8474e6d763d75ed96f3f2b98a25480cf2b9 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/aba4f94ac1832c7299c33e1b4fe5f87eef6dc8f1 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report