CVE-2021-23999 · cross-distro fix matrix

CVE-2021-23999: If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

Affects 8 Linux releases across 23 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-23999 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

firefox-esr→ fixed in78.10.0esr-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y firefox-esr
```
thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian bookworm

Source: Debian Security Tracker

firefox-esr→ fixed in78.10.0esr-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y firefox-esr
```
thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Debian trixie

Source: Debian Security Tracker

firefox-esr→ fixed in78.10.0esr-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y firefox-esr
```
thunderbird→ fixed in1:78.10.0-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y thunderbird
```

Alpine v3.20

Source: Alpine secdb

firefox-esr→ fixed in78.10.0-r0

apk update && apk add --upgrade firefox-esr

firefox→ fixed in88.0-r0
```
apk update && apk add --upgrade firefox
```

thunderbird→ fixed in91.3.2-r0

apk update && apk add --upgrade thunderbird

Alpine v3.21

Source: Alpine secdb

firefox-esr→ fixed in78.10.0-r0

apk update && apk add --upgrade firefox-esr

firefox→ fixed in88.0-r0
```
apk update && apk add --upgrade firefox
```

librewolf→ fixed in88.0-r0

apk update && apk add --upgrade librewolf

thunderbird→ fixed in91.3.2-r0

apk update && apk add --upgrade thunderbird

Alpine edge

Source: Alpine secdb

firefox-esr→ fixed in78.10.0-r0

apk update && apk add --upgrade firefox-esr

firefox→ fixed in88.0-r0
```
apk update && apk add --upgrade firefox
```

librewolf→ fixed in88.0-r0

apk update && apk add --upgrade librewolf

thunderbird→ fixed in91.3.2-r0

apk update && apk add --upgrade thunderbird

Alpine v3.18

Source: Alpine secdb

firefox-esr→ fixed in78.10.0-r0

apk update && apk add --upgrade firefox-esr

firefox→ fixed in88.0-r0
```
apk update && apk add --upgrade firefox
```

thunderbird→ fixed in91.3.2-r0

apk update && apk add --upgrade thunderbird

Alpine v3.19

Source: Alpine secdb

firefox-esr→ fixed in78.10.0-r0

apk update && apk add --upgrade firefox-esr

firefox→ fixed in88.0-r0
```
apk update && apk add --upgrade firefox
```

thunderbird→ fixed in91.3.2-r0

apk update && apk add --upgrade thunderbird

Are YOU affected by CVE-2021-23999?

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

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