CVE-2026-98975: In the Linux kernel, the following vulnerability has been resolved: xfs: stop exchanging reflink flags when exchanging mappings When an exchange covers both f

In the Linux kernel, the following vulnerability has been resolved: xfs: stop exchanging reflink flags when exchanging mappings When an exchange covers both f

In the Linux kernel, the following vulnerability has been resolved: xfs: stop exchanging reflink flags when exchanging mappings When an exchange covers both files from offset 0 to i_disk_size, xmi_can_exchange_reflink_flags() assumes every mapping moved and hands the reflink flag over to the other file. That assumption is wrong. A file can still own shared blocks past i_disk_size, e.g. after EXCHANGE_RANGE_TO_EOF sets a smaller size without unmapping anything. The flag is cleared anyway, and the next write to such a block happens in place instead of CoW, corrupting the other file that shares it. Commit a23eca88448e ("xfs: fix exchange-range reflink flag clearing issue with INO1_WRITTEN") fixed one instance of this. Rather than add another special case, stop moving the flags. xfs_exchmaps_ensure_reflink() already sets the flag on both inodes before the exchange, so both just keep it. Nothing sets CLEAR_INO{1,2}_REFLINK anymore. Intents logged by older kernels may still carry them; recovery already masks them off, so they stay in the log format mask and are ignored. XFS_IOC_SWAPEXT has the same problem: it moves the reflink flag from one inode to the other along with the ex

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 0.16%, higher than 5% 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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