In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid crash when inline data creation follows DIO write
When inode is created and written to using direct IO, there is nothing
to clear the EXT4_STATE_MAY_INLINE_DATA flag. Thus when inode gets
truncated later to say 1 byte and written using normal write, we will
try to store the data as inline data. This confuses the code later
because the inode now has both normal block and inline data allocated
and the confusion manifests for example as:
kernel BUG at fs/ext4/inode.c:2721!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 359 Comm: repro Not tainted 5.19.0-rc8-00001-g31ba1e3b8305-dirty #15
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014
RIP: 0010:ext4_writepages+0x363d/0x3660
RSP: 0018:ffffc90000ccf260 EFLAGS: 00010293
RAX: ffffffff81e1abcd RBX: 0000008000000000 RCX: ffff88810842a180
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc90000ccf650 R08: ffffffff81e17d58 R09: ffffed10222c680b
R10: dfffe910222c680c R11: 1ffff110222c680a R12: ffff888111634128
R13: ffffc90000ccf880 R14: 0000008410000000 R15: 0000000000000001
FS: 00007f72635d2640(0000) GS:ffff88811b000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000565243379180 CR3: 000000010aa74000 CR4: 0000000000150eb0
Call Trace:
do_writepages+0x397/0x640
filemap_fdatawrite_wbc+0x151/0x1b0
file_write_and_wait_range+0x1c9/0x2b0
ext4_sync_file+0x19e/0xa00
vfs_fsync_range+0x17b/0x190
ext4_buffered_write_iter+0x488/0x530
ext4_file_write_iter+0x449/0x1b90
vfs_write+0xbcd/0xf40
ksys_write+0x198/0x2c0
__x64_sys_write+0x7b/0x90
do_syscall_64+0x3d/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fix the problem by clearing EXT4_STATE_MAY_INLINE_DATA when we are doing
direct IO write to a file.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-05). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it