CVE-2026-104477 (GCVE-0-2026-104477)
Vulnerability from cvelistv5
Published
2026-10-02 23:28
Modified
2026-10-05 20:30
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
Showdown through 2.1.0 contains a cross-site scripting vulnerability in the makehtml link and image subparsers, which fail to escape double quotes in destination URLs placed into href and src attributes. Attackers can craft markdown links or images containing a double quote followed by onerror or onmouseover handlers to execute script when victims view rendered HTML.
Impacted products
Vendor Product Version
showdownjs showdown Version: 0   ≤ 2.1.0
Create a notification for this product.
Show details on NVD website


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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


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