CVE-2021-40083 · cross-distro fix matrix

CVE-2021-40083: Knot Resolver before 5.3.2 is prone to an assertion failure, triggerable by a remote attacker in an edge case (NSEC3 with too many iterations used for a positive wildcard proof).

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-40083 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

knot-resolver→ fixed in5.3.1-1+deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y knot-resolver
```

Debian bookworm

Source: Debian Security Tracker

knot-resolver→ fixed in5.4.1-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y knot-resolver
```

Debian trixie

Source: Debian Security Tracker

knot-resolver→ fixed in5.4.1-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y knot-resolver
```

Are YOU affected by CVE-2021-40083?

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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