Summary
generated automatically from NVD dataPython-Markdown versions 3.0 through 3.11.2 have an algorithmic complexity flaw (CWE-407) in inline link parsing. A remote attacker can submit short Markdown containing repeated [ or ![ characters with no matching bracket, which makes LinkInlineProcessor.getText() and getLink() perform quadratic scans. This can keep workers busy for minutes and exhaust CPU, causing denial of service. The CVSS v3.1 score is 7.5 (HIGH).
NVD 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.
EPSS · FIRST.org
0.42%probability of exploitation in the next 30 days
Higher than 36% of scored CVEs
EPSS (Exploit Prediction Scoring System) estimates, from observed exploitation activity, how likely a CVE is to be exploited in the next 30 days. It complements CVSS, which measures severity, not likelihood. Score of 2026-10-30, recomputed daily by FIRST.org.
CVSS v3.1 Score
Information
- Published
- 29 oct. 2026
- Updated
- 29 oct. 2026
- Status
- Awaiting Analysis
- Source
- disclosure@vulncheck.com
Weaknesses (CWE)
References (5)
Similar CVEs
Other vulnerabilities of type CWE-407
Know which CVEs hit the versions you run.
Add the product and its version: cveo.tech lists the CVEs that affect it right away, then alerts you by email when a new one affects it — including before NVD has finished its analysis. Free, an account is all it takes.