CVE-2025-21815 · cross-distro fix matrix

CVE-2025-21815: In the Linux kernel, the following vulnerability has been resolved: mm/compaction: fix UBSAN shift-out-of-bounds warning syzkaller reported a UBSAN shift-out-of-bounds warning of (1UL << order) in isolate_freepages_block(). The bogus compound_order can be any value because it is union with flags.

Affects 1 Linux release across 1 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-21815 has a known fix. Run the listed command on that distro to remediate.

Debian trixie

Source: Debian Security Tracker

linux→ fixed in6.12.15-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Are YOU affected by CVE-2025-21815?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

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