CVE-2021-24031 · cross-distro fix matrix

CVE-2021-24031: In the Zstandard command-line utility prior to v1.4.1, output files were created with default permissions. Correct file permissions (matching the input) would only be set at completion time. Output files could therefore be readable or writable to unintended parties.

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-24031 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libzstd→ fixed in1.4.8+dfsg-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libzstd
```

Debian bookworm

Source: Debian Security Tracker

libzstd→ fixed in1.4.8+dfsg-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libzstd
```

Debian trixie

Source: Debian Security Tracker

libzstd→ fixed in1.4.8+dfsg-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libzstd
```

Alpine v3.20

Source: Alpine secdb

zstd→ fixed in1.4.1-r0
```
apk update && apk add --upgrade zstd
```

Alpine v3.21

Source: Alpine secdb

zstd→ fixed in1.4.1-r0
```
apk update && apk add --upgrade zstd
```

Alpine edge

Source: Alpine secdb

zstd→ fixed in1.4.1-r0
```
apk update && apk add --upgrade zstd
```

Alpine v3.18

Source: Alpine secdb

zstd→ fixed in1.4.1-r0
```
apk update && apk add --upgrade zstd
```

Alpine v3.19

Source: Alpine secdb

zstd→ fixed in1.4.1-r0
```
apk update && apk add --upgrade zstd
```

Are YOU affected by CVE-2021-24031?

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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