CVE-2021-43827 (GCVE-0-2021-43827)

Vulnerability from cvelistv5 – Published: 2021-12-14 22:20 – Updated: 2024-08-04 04:03
VLAI
Title
Inline footnotes wrapped in <a> tags can cause errors in discourse-footnotes
Summary
discourse-footnote is a library providing footnotes for posts in Discourse. ### Impact When posting an inline footnote wrapped in `<a>` tags (e.g. `<a>^[footnote]</a>`, the resulting rendered HTML would include a nested `<a>`, which is stripped by Nokogiri because it is not valid. This then caused a javascript error on topic pages because we were looking for an `<a>` element inside the footnote reference span and getting its ID, and because it did not exist we got a null reference error in javascript. Users are advised to update to version 0.2. As a workaround editing offending posts from the rails console or the database console for self-hosters, or disabling the plugin in the admin panel can mitigate this issue.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-755 - Improper Handling of Exceptional Conditions
Assigner
GitHub_M CNA
References
Impacted products
Show details on NVD website
To clipboard 

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