CVE-2021-33503 · cross-distro fix matrix

CVE-2021-33503: An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redire

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-33503 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

python-urllib3→ fixed in1.26.5-1~exp1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python-urllib3
```

Debian bookworm

Source: Debian Security Tracker

python-urllib3→ fixed in1.26.5-1~exp1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python-urllib3
```

Debian trixie

Source: Debian Security Tracker

python-urllib3→ fixed in1.26.5-1~exp1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y python-urllib3
```

Are YOU affected by CVE-2021-33503?

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