CVE-2021-3507 · cross-distro fix matrix

CVE-2021-3507: A heap buffer overflow was found in the floppy disk emulator of QEMU up to 6.0.0 (including). It could occur in fdctrl_transfer_handler() in hw/block/fdc.c while processing DMA read data transfers from the floppy drive to the guest system. A privileged guest user could use this flaw to crash the QEM

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-3507 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+deb11u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Debian bookworm

Source: Debian Security Tracker

qemu→ fixed in1:7.1+dfsg-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Debian trixie

Source: Debian Security Tracker

qemu→ fixed in1:7.1+dfsg-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Alpine v3.20

Source: Alpine secdb

qemu→ fixed in6.1.0-r0
```
apk update && apk add --upgrade qemu
```

Alpine v3.21

Source: Alpine secdb

qemu→ fixed in6.1.0-r0
```
apk update && apk add --upgrade qemu
```

Alpine edge

Source: Alpine secdb

qemu→ fixed in6.1.0-r0
```
apk update && apk add --upgrade qemu
```

Alpine v3.18

Source: Alpine secdb

qemu→ fixed in6.1.0-r0
```
apk update && apk add --upgrade qemu
```

Alpine v3.19

Source: Alpine secdb

qemu→ fixed in6.1.0-r0
```
apk update && apk add --upgrade qemu
```

Are YOU affected by CVE-2021-3507?

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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