CVE-2025-38221: In the Linux kernel, the following vulnerability has been resolved: ext4: fix out of bounds punch offset Punching a hole with a start offset that exceeds max

In the Linux kernel, the following vulnerability has been resolved: ext4: fix out of bounds punch offset Punching a hole with a start offset that exceeds max_

In the Linux kernel, the following vulnerability has been resolved: ext4: fix out of bounds punch offset Punching a hole with a start offset that exceeds max_end is not permitted and will result in a negative length in the truncate_inode_partial_folio() function while truncating the page cache, potentially leading to undesirable consequences. A simple reproducer: truncate -s 9895604649994 /mnt/foo xfs_io -c "pwrite 8796093022208 4096" /mnt/foo xfs_io -c "fpunch 8796093022213 25769803777" /mnt/foo kernel BUG at include/linux/highmem.h:275! Oops: invalid opcode: 0000 [#1] SMP PTI CPU: 3 UID: 0 PID: 710 Comm: xfs_io Not tainted 6.15.0-rc3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:zero_user_segments.constprop.0+0xd7/0x110 RSP: 0018:ffffc90001cf3b38 EFLAGS: 00010287 RAX: 0000000000000005 RBX: ffffea0001485e40 RCX: 0000000000001000 RDX: 000000000040b000 RSI: 0000000000000005 RDI: 000000000040b000 RBP: 000000000040affb R08: ffff888000000000 R09: ffffea0000000000 R10: 0000000000000003 R11: 00000000fffc7fc5 R12: 0000000000000005 R13: 000000000040affb R14: ffffea0001485e40 R15: ffff888031cd3000 FS: 00007

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.17%, higher than 6% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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