Answer in brief
CVE-2026-43288 records a Unknown severity vulnerability in ext4: move ext4_percpu_param_init() before ext4_mb_init(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=d5e03cbb0c88cd1be39f2adc37d602230045964b <0b3d80c56957862ba477ca0ce30c12cad9179c2b || >=d5e03cbb0c88cd1be39f2adc37d602230045964b <0d5fcb063cdabb9aeaa8554b7fedad2092c4150e || >=d5e03cbb0c88cd1be39f2adc37d602230045964b <9e9fb259bcddf459a0168f4a964e979e500a68a5 || >=d5e03cbb0c88cd1be39f2adc37d602230045964b <bf5b609524497c195f801cd5707252384aed8149 || >=d5e03cbb0c88cd1be39f2adc37d602230045964b <aec095f3cc6cf209effd93278ce35be27db81d73 || >=d5e03cbb0c88cd1be39f2adc37d602230045964b <270564513489d98b721a1e4a10017978d5213bff | 0b3d80c56957862ba477ca0ce30c12cad9179c2b, 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e, 9e9fb259bcddf459a0168f4a964e979e500a68a5, bf5b609524497c195f801cd5707252384aed8149, aec095f3cc6cf209effd93278ce35be27db81d73, 270564513489d98b721a1e4a10017978d5213bff |
| Linux/Linuxgeneric | 3.17 | Not reported |
Published upstream
May 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 14, 2026
In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.
Quoted source text, attributed separately from HOL analysis.