CVE-2021-3733 · cross-distro fix matrix

CVE-2021-3733: There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is se

Affects 3 Linux releases across 4 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-3733 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-2urgency: 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 in7.3.5+dfsg-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```

Debian trixie

Source: Debian Security Tracker

pypy3→ fixed in7.3.5+dfsg-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y pypy3
```

Are YOU affected by CVE-2021-3733?

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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