CVE-2026-111759
markdown-it: Quadratic complexity in smartquotes with unmatched closing quotes
Description
markdown-it is a Markdown parser. Prior to 14.3.2 and 15.0.2, when typographer: true is enabled, specially crafted Markdown can cause quadratic processing time in the smartquotes rule, potentially leading to denial of service in applications processing untrusted input. Many opening double quotes followed by unmatched closing single quotes cause repeated scans of the entire opener stack. The same issue occurs with the quote types reversed. The default configuration (typographer: false) is not affected, but this option is enabled with high probability. This issue is fixed in versions 14.3.2 and 15.0.2.
INFO
Published Date :
Oct. 19, 2026, 6:17 p.m.
Last Modified :
Oct. 19, 2026, 7:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update markdown-it to version 14.3.2 or later.
- Update markdown-it to version 15.0.2 or later.
- Disable typographer mode if updating is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-111759.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-111759 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-111759
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-111759 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-111759 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 19, 2026
Action Type Old Value New Value Added Reference https://github.com/markdown-it/markdown-it/security/advisories/GHSA-r7fv-28h4-cvq7 Added SSVC {'id': 'CVE-2026-111759', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-10-19T18:22:34.328088Z'} -
New CVE Received by [email protected]
Oct. 19, 2026
Action Type Old Value New Value Added Description markdown-it is a Markdown parser. Prior to 14.3.2 and 15.0.2, when typographer: true is enabled, specially crafted Markdown can cause quadratic processing time in the smartquotes rule, potentially leading to denial of service in applications processing untrusted input. Many opening double quotes followed by unmatched closing single quotes cause repeated scans of the entire opener stack. The same issue occurs with the quote types reversed. The default configuration (typographer: false) is not affected, but this option is enabled with high probability. This issue is fixed in versions 14.3.2 and 15.0.2. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-407 Added CWE CWE-400 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/111xxx/CVE-2026-111759.json">CVE-2026-111759</a> Added Reference https://github.com/markdown-it/markdown-it/commit/1b379c1b6d0522421bd1a51b77337c79af2c8670 Added Reference https://github.com/markdown-it/markdown-it/commit/cf27366035edf9196667110c47d9d67b030a4152 Added Reference https://github.com/markdown-it/markdown-it/commit/daf5a3c32303e5d9de01b12eeb725fb5990b8162 Added Reference https://github.com/markdown-it/markdown-it/releases/tag/14.3.2 Added Reference https://github.com/markdown-it/markdown-it/releases/tag/15.0.2 Added Reference https://github.com/markdown-it/markdown-it/security/advisories/GHSA-r7fv-28h4-cvq7