CVE-2026-48591

Improper Neutralization of Script in Attributes in a Web Page vulnerability in pragdave earmark allows stored cross-site scripting via unescaped HTML attribute values. 'Elixir.Earmark.Transform':_make_att1/2 in lib/earmark/transform.ex splices attribute values verbatim between two literal " bytes: [" ", name, "=\"", value, "\""]. Text nodes are routed through the existing escape function which encodes " as ", but attribute values never visit that path. A markdown link whose URL or title contains a bare " closes the attribute early and lets the trailing bytes be parsed by the browser as fresh HTML attributes. For example, [click](http://example.com/?a=x" onerror="alert(1)) renders as <a href="http://example.com/?a=x" onerror="alert(1)">click</a>, executing arbitrary JavaScript in the victim's browser. The earmark library is no longer maintained and has been retired on Hex. No patched version will be released. All releases from 1.4.1 onward are affected, and users should migrate to a maintained Markdown library such as MDEx. This issue affects earmark from 1.4.1 onward.

CVSS

No CVSS.

References

Link	Resource
https://cna.erlef.org/cves/CVE-2026-48591.html
https://osv.dev/vulnerability/EEF-CVE-2026-48591

Configurations

No configuration.

History

17 Jun 2026, 19:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 18:18

Updated : 2026-06-22 18:45

NVD link : CVE-2026-48591

Mitre link : CVE-2026-48591

CVE.ORG link : CVE-2026-48591

JSON object : View

Products Affected

No product.

CWE

CWE-83

Improper Neutralization of Script in Attributes in a Web Page

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