CVE-2025-6069

MEDIUM
Published Jun 17, 2025 Modified Apr 15, 2026 CWE-1333

Description

The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.

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CVSS v3.1 Score

4.3
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Weakness Type (CWE)

CWE-1333 CWE-1333

References

Frequently Asked Questions

What is CVE-2025-6069? +
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service. It has a CVSS v3.1 base score of 4.3 (MEDIUM).
How severe is CVE-2025-6069? +
CVE-2025-6069 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2025-6069? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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