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Appaloosa Scout

Vulnerability · NVD

CVE-2021-3733

MEDIUM 6.5 Vendor bulletin scale — NVD CVSS pending

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 sent by the server to the client. The greatest threat that this flaw poses is to application availability.

Attack vector : Network No user interaction
Show raw CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS 4.68% above median percentile 90.9%

Tracked apps referencing this CVE

For each app: the affected range, the fixing version, and where the tracked app stands today.

  • Python 3.12 Windows winget:Python.Python.3.12
    Affected Fixed in Latest tracked 3.12.10 undetermined

NVD references 20 distinct products for this CVE — only those tracked by Scout (mobile and desktop catalog apps) are listed above. Libraries, servers and out-of-scope products do not appear here. Full list on NVD ↗

Vulnerable CPE configurations (5)
Vendor Product Versions
python python
All platforms (wildcard)
<3.6.14
python python
All platforms (wildcard)
≥3.7.0 <3.7.11
python python
All platforms (wildcard)
≥3.8.0 <3.8.10
python python
All platforms (wildcard)
≥3.9.0 <3.9.5
python python
All platforms (wildcard)
View on NVD ↗ Advisory · bugs.python.org Advisory · github.com Advisory · ubuntu.com