What is the CVSS score of CVE-2021-43827?

CVE-2021-43827 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L. EPSS exploitation probability: 0.8%.

Is there a patch available for CVE-2021-43827?

Yes, a patch is available for CVE-2021-43827. Update the affected software to the latest version immediately.

Discourse CVE-2021-43827

MEDIUM

Improper Handling of Exceptional Conditions (CWE-755)

2021-12-14 security-advisories@github.com

Information Disclosure Discourse Discourse Footnote

4.3

CVSS 3.1 · Vendor: github

Severity by source

Vendor (github) PRIMARY

4.3 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Primary rating from Vendor (github) · only source for this CVE.

CVSS VectorVendor: github

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low

Lifecycle Timeline

CVE Published

Dec 14, 2021 - 23:15 cve.org

MEDIUM 4.3

DescriptionCVE.org

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.

AnalysisAI

discourse-footnote is a library providing footnotes for posts in Discourse. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity.

Technical ContextAI

This vulnerability is classified under CWE-755. 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. Affected products include: Discourse Discourse Footnote. Version information: version 0.2..

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.