Vulnerability library
Security checkAugust 07, 2026

showdown allows stored cross-site scripting through table header ID injection

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Medium severitynpmshowdown

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Description

showdown contains a stored cross-site scripting vulnerability in the parseHeaders function of src/subParsers/makehtml/tables.js that fails to properly escape table header ID attributes.

Recommendation

No fix is available yet. Followings are affected versions:

  • <= 2.1.0

References

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See something that needs correcting? Let us knowUpdated August 07, 2026