CVE-2021-28861 · cross-distro fix matrix

CVE-2021-28861: Python 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure. NOTE: this is disputed by a third party because the http.server.html documentation page states "Warnin

Affects 3 Linux releases across 5 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-28861 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

pypy3→ fixed in7.3.5+dfsg-2+deb11u4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```
python3.9→ fixed in3.9.2-1+deb11u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python3.9
```

Debian bookworm

Source: Debian Security Tracker

pypy3→ fixed in7.3.10+dfsg-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y pypy3
```
python3.11→ fixed in3.11.0~b4-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y python3.11
```

Debian trixie

Source: Debian Security Tracker

pypy3→ fixed in7.3.10+dfsg-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y pypy3
```

Are YOU affected by CVE-2021-28861?

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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