CVE-2026-40211 · cross-distro fix matrix

CVE-2026-40211: An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory

Affects 2 Linux releases across 2 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2026-40211 has a known fix. Run the listed command on that distro to remediate.

Debian trixie

Source: Debian Security Tracker

dnsdist→ fixed in1.9.15-0+deb13u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y dnsdist
```

Alpine edge

Source: Alpine secdb

dnsdist→ fixed in2.0.7-r0
```
apk update && apk add --upgrade dnsdist
```

Are YOU affected by CVE-2026-40211?

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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