CVE-2021-43827
Discourse Footnote Xss
Description
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.
INFO
Published Date :
Dec. 14, 2021, 11:15 p.m.
Last Modified :
Dec. 29, 2021, 8:31 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
1.4
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-43827.
| URL | Resource |
|---|---|
| https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab | Patch Third Party Advisory |
| https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-43827 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-43827 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Initial Analysis by [email protected]
Dec. 29, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:N/I:N/A:P) Changed Reference Type https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab No Types Assigned https://github.com/discourse/discourse-footnote/commit/796617e0131277011207541313522cd1946661ab Patch, Third Party Advisory Changed Reference Type https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57 No Types Assigned https://github.com/discourse/discourse-footnote/security/advisories/GHSA-58vr-c56v-qr57 Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:discourse:discourse_footnote:*:*:*:*:*:discourse:*:* versions up to (excluding) 0.2
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-43827 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-43827
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.08 }} 0.01%
score
0.31180
percentile