CVE-2026-90004: In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: handle region split failure in apply_min_nr_regions() damon_apply_min_nr

In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: handle region split failure in apply_min_nr_regions() damon_apply_min_nr_re

In the Linux kernel, the following vulnerability has been resolved: mm/damon/core: handle region split failure in apply_min_nr_regions() damon_apply_min_nr_regions() repeatedly split each region until its size becomes small enough to meet the user-defined low limit of the number of regions. The loop assumes the split operation (damon_split_region_at()) will always succeed and create the new region. But the operation could silently fail for memory allocation failures, for example. If such failure happens and the region was the last region, the linked list-based next region fetching returns invalid pointer. As a result, invalid memory dereference and corruption could happen. Even if the corner case is handled, it imposes stress to the allocator by trying split regions for other targets. Fix the issue by breaking all the loops for any region split failure. This means there could be a min_nr_regions violation. It will only rarely happen since the allocation is arguably too small to fail. Even if it happens, it is only temporal. damon_apply_min_nr_regions() will be called again after the aggregation interval. The user impact of the issue should be minor, since the allocatio

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 0.20%, higher than 9% 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

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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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