CVE-2026-80656
Received
Received - Intake
HFS+ btree node size validation failure
Vulnerability report for CVE-2026-80656, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-28
Last updated on: 2026-08-29
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
hfsplus: Add a sanity check for btree node size
Syzbot reported an uninit-value bug in [1] with a corrupted HFS+ image,
during the file system mounting process, specifically while loading the
catalog, a corrupted node_size value of 1 caused the rec_off argument
passed to hfs_bnode_read_u16() (within hfs_bnode_find()) to be excessively
large. Consequently, the function failed to return a valid value to
initialize the off variable, triggering the bug [1].
Every node starts from BTree node descriptor: struct hfs_bnode_desc.
So, the size of node cannot be lesser than that. However, technical
specification declares that: "The node size (which is expressed in bytes)
must be power of two, from 512 through 32,768, inclusive." Add a check
for btree node size base on technical specification.
[1]
BUG: KMSAN: uninit-value in hfsplus_bnode_find+0x141c/0x1600 fs/hfsplus/bnode.c:584
hfsplus_bnode_find+0x141c/0x1600 fs/hfsplus/bnode.c:584
hfsplus_btree_open+0x169a/0x1e40 fs/hfsplus/btree.c:382
hfsplus_fill_super+0x111f/0x2770 fs/hfsplus/super.c:553
get_tree_bdev_flags+0x6e6/0x920 fs/super.c:1694
get_tree_bdev+0x38/0x50 fs/super.c:1717
hfsplus_get_tree+0x35/0x40 fs/hfsplus/super.c:709
vfs_get_tree+0xb3/0x5d0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
