CVE-2021-39240 · cross-distro fix matrix

CVE-2021-39240: An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It does not ensure that the scheme and path portions of a URI have the expected characters. For example, the authority field (as observed on a target HTTP/2 server) might differ from what the routing rules

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-39240 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

haproxy→ fixed in2.2.9-2+deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y haproxy
```

Debian bookworm

Source: Debian Security Tracker

haproxy→ fixed in2.2.16-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y haproxy
```

Debian trixie

Source: Debian Security Tracker

haproxy→ fixed in2.2.16-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y haproxy
```

Are YOU affected by CVE-2021-39240?

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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