CVE-2021-41095
Discourse XSS Vulnerability Through User Input in Error Messages
Description
Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags.
INFO
Published Date :
Sept. 27, 2021, 8:15 p.m.
Last Modified :
Nov. 7, 2023, 3:38 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
2.7
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-2021-41095.
| URL | Resource |
|---|---|
| https://github.com/discourse/discourse/pull/14434/commits/40b776b9d39c41d9273d01eecf8fe03aa39fcb59 | Patch Third Party Advisory |
| https://github.com/discourse/discourse/security/advisories/GHSA-qvqx-2h7w-m479 | 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-2021-41095 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-41095 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 -
CVE Modified by [email protected]
Nov. 07, 2023
Action Type Old Value New Value Changed Description Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags. Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags. -
Initial Analysis by [email protected]
Oct. 06, 2021
Action Type Old Value New Value Added CVSS V2 Metadata Victim must voluntarily interact with attack mechanism Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:N/I:P/A:N) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Changed Reference Type https://github.com/discourse/discourse/pull/14434/commits/40b776b9d39c41d9273d01eecf8fe03aa39fcb59 No Types Assigned https://github.com/discourse/discourse/pull/14434/commits/40b776b9d39c41d9273d01eecf8fe03aa39fcb59 Patch, Third Party Advisory Changed Reference Type https://github.com/discourse/discourse/security/advisories/GHSA-qvqx-2h7w-m479 No Types Assigned https://github.com/discourse/discourse/security/advisories/GHSA-qvqx-2h7w-m479 Third Party Advisory Added CWE NIST CWE-79 Added CPE Configuration OR *cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* versions up to (including) 2.7.7 *cpe:2.3:a:discourse:discourse:2.8.0:beta1:*:*:*:*:*:* *cpe:2.3:a:discourse:discourse:2.8.0:beta2:*:*:*:*:*:* *cpe:2.3:a:discourse:discourse:2.8.0:beta3:*:*:*:*:*:* *cpe:2.3:a:discourse:discourse:2.8.0:beta4:*:*:*:*:*:* *cpe:2.3:a:discourse:discourse:2.8.0:beta5:*:*:*:*:*:* *cpe:2.3:a:discourse:discourse:2.8.0:beta6:*:*:*:*:*:*
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-41095 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-2021-41095
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.07 }} 0.00%
score
0.29193
percentile