CVE-2021-43827

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Summary

CVECVE-2021-43827
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-12-14 23:15:00 UTC
Updated2021-12-29 20:31:00 UTC
Descriptiondiscourse-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.

Risk And Classification

Problem Types: CWE-755

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Discourse Discourse Footnote All All All All

References

ReferenceSourceLinkTags
SECURITY: Fix malicious footnote causing clientside errors (#27) · discourse/discourse-footnote@796617e · GitHub MISC github.com
Malicious footnote markup may cause client side errors. · Advisory · discourse/discourse-footnote · GitHub CONFIRM github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

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