CVE-2020-9391 · cross-distro fix matrix

CVE-2020-9391: An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It ignores the top byte in the address passed to the brk system call, potentially moving the memory break downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been

Affects 3 Linux releases across 3 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2020-9391 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

linux→ fixed in5.5.13-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Debian bookworm

Source: Debian Security Tracker

linux→ fixed in5.5.13-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Debian trixie

Source: Debian Security Tracker

linux→ fixed in5.5.13-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Are YOU affected by CVE-2020-9391?

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