CVE-2021-21704 · cross-distro fix matrix

CVE-2021-21704: In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using Firebird PDO driver extension, a malicious database server could cause crashes in various database functions, such as getAttribute(), execute(), fetch() and others by returning invalid response data that is not

Affects 1 Linux release across 1 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-21704 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

php7.4→ fixed in7.4.21-1+deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y php7.4
```

Are YOU affected by CVE-2021-21704?

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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