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VULNERABILITIES

CVE-2019-25781 Details

Description

Python-Markdown 3.0 through 3.11.2 contains an algorithmic complexity vulnerability in inline link parsing that allows remote attackers to exhaust CPU through unmatched brackets. Attackers can submit short Markdown containing repeated [ or ![ characters, forcing LinkInlineProcessor.getText() and getLink() into quadratic scans that keep workers busy for minutes.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:7.5 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://github.com/Python-Markdown/markdown/issues/1654 CISA-ADP
https://github.com/Python-Markdown/markdown [email protected]
https://github.com/Python-Markdown/markdown/blob/b41e0aaf1181f1a8cb200cf5a815aad7c0020d23/markdown/inlinepatterns.py#L1155-L1172 [email protected]
https://github.com/Python-Markdown/markdown/issues/1654 [email protected]
https://github.com/Python-Markdown/markdown/issues/798 [email protected]

see all 6 references

Weakness Enumeration

CWE-IDCWE NameSource
CWE-407Inefficient Algorithmic Complexity[email protected]

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2019-25781
NVD Published Date:
Oct 29, 2026
NVD Last Modified:
Nov 3, 2026
Source:
[email protected]