CVE-2021-3748 · cross-distro fix matrix

CVE-2021-3748: A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-3748 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

qemu→ fixed in1:5.2+dfsg-11+deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Debian bookworm

Source: Debian Security Tracker

qemu→ fixed in1:6.1+dfsg-6urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Debian trixie

Source: Debian Security Tracker

qemu→ fixed in1:6.1+dfsg-6urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Are YOU affected by CVE-2021-3748?

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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