CVE-2021-43529 · cross-distro fix matrix

CVE-2021-43529: Thunderbird versions prior to 91.3.0 are vulnerable to the heap overflow described in CVE-2021-43527 when processing S/MIME messages. Thunderbird versions 91.3.0 and later will not call the vulnerable code when processing S/MIME messages that contain certificates with DER-encoded DSA or RSA-PSS sign

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-43529 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

thunderbird→ fixed in1:91.4.1-1~deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian bookworm

Source: Debian Security Tracker

thunderbird→ fixed in1:91.3.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian trixie

Source: Debian Security Tracker

thunderbird→ fixed in1:91.3.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Are YOU affected by CVE-2021-43529?

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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