CVE-2025-43859 · cross-distro fix matrix

CVE-2025-43859: h11 is a Python implementation of HTTP/1.1. Prior to version 0.16.0, a leniency in h11's parsing of line terminators in chunked-coding message bodies can lead to request smuggling vulnerabilities under certain conditions. This issue has been patched in version 0.16.0. Since exploitation requires the

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

Fix per ecosystem

Each block below is a distro release where CVE-2025-43859 has a known fix. Run the listed command on that distro to remediate.

Debian bookworm

Source: Debian Security Tracker

python-h11→ fixed in0.14.0-1.1~deb12u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python-h11
```

Debian trixie

Source: Debian Security Tracker

python-h11→ fixed in0.14.0-1.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python-h11
```

Are YOU affected by CVE-2025-43859?

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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