CVE-2021-3631 · cross-distro fix matrix

CVE-2021-3631: A flaw was found in libvirt while it generates SELinux MCS category pairs for VMs' dynamic labels. This flaw allows one exploited guest to access files labeled for another guest, resulting in the breaking out of sVirt confinement. The highest threat from this vulnerability is to confidentiality and

Affects 8 Linux releases across 8 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-3631 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libvirt→ fixed in7.0.0-3+deb11u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvirt
```

Debian bookworm

Source: Debian Security Tracker

libvirt→ fixed in7.6.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvirt
```

Debian trixie

Source: Debian Security Tracker

libvirt→ fixed in7.6.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvirt
```

Alpine v3.20

Source: Alpine secdb

libvirt→ fixed in7.5.0-r0
```
apk update && apk add --upgrade libvirt
```

Alpine v3.21

Source: Alpine secdb

libvirt→ fixed in7.5.0-r0
```
apk update && apk add --upgrade libvirt
```

Alpine edge

Source: Alpine secdb

libvirt→ fixed in7.5.0-r0
```
apk update && apk add --upgrade libvirt
```

Alpine v3.18

Source: Alpine secdb

libvirt→ fixed in7.5.0-r0
```
apk update && apk add --upgrade libvirt
```

Alpine v3.19

Source: Alpine secdb

libvirt→ fixed in7.5.0-r0
```
apk update && apk add --upgrade libvirt
```

Are YOU affected by CVE-2021-3631?

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

Continuous monitoring beats manual checking

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