CVE-2021-20255 · cross-distro fix matrix

CVE-2021-20255: A stack overflow via an infinite recursion vulnerability was found in the eepro100 i8255x device emulator of QEMU. This issue occurs while processing controller commands due to a DMA reentry issue. This flaw allows a guest user or process to consume CPU cycles or crash the QEMU process on the host,

Affects 6 Linux releases across 6 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-20255 has a known fix. Run the listed command on that distro to remediate.

Debian trixie

Source: Debian Security Tracker

qemu→ fixed in1:8.1.0+ds-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y qemu
```

Alpine v3.20

Source: Alpine secdb

qemu→ fixed in6.0.0-r1
```
apk update && apk add --upgrade qemu
```

Alpine v3.21

Source: Alpine secdb

qemu→ fixed in6.0.0-r1
```
apk update && apk add --upgrade qemu
```

Alpine edge

Source: Alpine secdb

qemu→ fixed in6.0.0-r1
```
apk update && apk add --upgrade qemu
```

Alpine v3.18

Source: Alpine secdb

qemu→ fixed in6.0.0-r1
```
apk update && apk add --upgrade qemu
```

Alpine v3.19

Source: Alpine secdb

qemu→ fixed in6.0.0-r1
```
apk update && apk add --upgrade qemu
```

Are YOU affected by CVE-2021-20255?

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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