CVE-2021-28834 · cross-distro fix matrix

CVE-2021-28834: Kramdown before 2.3.1 does not restrict Rouge formatters to the Rouge::Formatters namespace, and thus arbitrary classes can be instantiated.

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-28834 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

ruby-kramdown→ fixed in2.3.0-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ruby-kramdown
```

Debian bookworm

Source: Debian Security Tracker

ruby-kramdown→ fixed in2.3.0-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ruby-kramdown
```

Debian trixie

Source: Debian Security Tracker

ruby-kramdown→ fixed in2.3.0-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ruby-kramdown
```

Are YOU affected by CVE-2021-28834?

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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