CVE-2026-71488

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Source
https://cve.org/CVERecord?id=CVE-2026-71488
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-71488.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-71488
Aliases
Downstream
Published
2026-08-06T20:37:17.488Z
Modified
2026-08-09T03:30:42.488116434Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
league/commonmark: Quadratic-time denial of service when parsing crafted Markdown
Details

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.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71488.json",
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-1050",
        "CWE-407"
    ]
}
References

Affected packages

Git / github.com/thephpleague/commonmark

Affected ranges

Type
GIT
Repo
https://github.com/thephpleague/commonmark
Events
Introduced
c352207aab15706a1ca9c25e5bd30c847899a0c9
Fixed
a6ef6cdc308dfa39a34239c35818e75892a0e6a8
Fixed
a70979ea0d7d3377bd7127536748454a922bf5eb
Fixed
c97b02e5e652b992033b93ba5d6182f706343fc6
Fixed
5703d83ba3da3b2e356a5fedc848ed6d8ffb6529
Database specific 
{
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0.6.0"
        },
        {
            "fixed": "2.9.0"
        }
    ]
}

Affected versions

0.*
0.10.0
0.11.0
0.11.1
0.11.2
0.11.3
0.12.0
0.13.0
0.13.1
0.13.2
0.13.3
0.13.4
0.14.0
0.15.0
0.15.1
0.15.2
0.15.3
0.15.4
0.15.5
0.15.6
0.15.7
0.16.0
0.17.0
0.17.2
0.17.4
0.18.1
0.6.0
0.6.1
0.7.0
0.7.1
0.8.0
0.9.0
2.*
2.0.0
2.0.0-beta1
2.0.0-beta2
2.0.0-beta3
2.0.0-rc1
2.0.0-rc2
2.0.1
2.0.2
2.1.0
2.2.0
2.3.0
2.4.0
2.5.0
2.6.0
2.7.0
2.8.0
2.8.1
2.8.2
2.8.3

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-71488.json"