U.S. flag   An official website of the United States government
Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock (Dot gov) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-71488 Detail

Description

league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 0.6.0 until 2.9.0, specially crafted Markdown lines can cause the parser to have quadratic time complexity when converting, because several parsing paths repeatedly rescan growing portions of a line to translate between character positions and byte positions, and the Autolink extension can also copy and validate the remaining line at every URL-like prefix, allowing an attacker who can submit Markdown for conversion to consume disproportionate CPU time with a comparatively small request. This issue is fixed in 2.9.0.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to [email protected].

URL Source(s) Tag(s)
https://github.com/thephpleague/commonmark/commit/a6ef6cdc308dfa39a34239c35818e75892a0e6a8 GitHub, Inc.
https://github.com/thephpleague/commonmark/commit/a70979ea0d7d3377bd7127536748454a922bf5eb GitHub, Inc.
https://github.com/thephpleague/commonmark/commit/c97b02e5e652b992033b93ba5d6182f706343fc6 GitHub, Inc.
https://github.com/thephpleague/commonmark/releases/tag/2.9.0 GitHub, Inc.
https://github.com/thephpleague/commonmark/security/advisories/GHSA-2q4p-g7hv-5rgv GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-407 Inefficient Algorithmic Complexity GitHub, Inc.  
CWE-1050 Excessive Platform Resource Consumption within a Loop GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-71488
NVD Published Date:
08/06/2026
NVD Last Modified:
08/06/2026
Source:
GitHub, Inc.