CVE-2021-23991 · cross-distro fix matrix

CVE-2021-23991: If a Thunderbird user has previously imported Alice's OpenPGP key, and Alice has extended the validity period of her key, but Alice's updated key has not yet been imported, an attacker may send an email containing a crafted version of Alice's key with an invalid subkey, Thunderbird might subsequentl

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-23991 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian bookworm

Source: Debian Security Tracker

thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian trixie

Source: Debian Security Tracker

thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Are YOU affected by CVE-2021-23991?

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

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