CVE-2021-39197
"Remote Code Execution via CSRF in better_errors"
Description
better_errors is an open source replacement for the standard Rails error page with more information rich error pages. It is also usable outside of Rails in any Rack app as Rack middleware. better_errors prior to 2.8.0 did not implement CSRF protection for its internal requests. It also did not enforce the correct "Content-Type" header for these requests, which allowed a cross-origin "simple request" to be made without CORS protection. These together left an application with better_errors enabled open to cross-origin attacks. As a developer tool, better_errors documentation strongly recommends addition only to the `development` bundle group, so this vulnerability should only affect development environments. Please ensure that your project limits better_errors to the `development` group (or the non-Rails equivalent). Starting with release 2.8.x, CSRF protection is enforced. It is recommended that you upgrade to the latest release, or minimally to "~> 2.8.3". There are no known workarounds to mitigate the risk of using older releases of better_errors.
INFO
Published Date :
Sept. 7, 2021, 6:15 p.m.
Last Modified :
Nov. 21, 2024, 6:18 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
5.9
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-2021-39197.
| URL | Resource |
|---|---|
| https://github.com/BetterErrors/better_errors/commit/8e8e796bfbde4aa088741823c8a3fc6df2089bb0 | Patch Third Party Advisory |
| https://github.com/BetterErrors/better_errors/discussions/507 | Third Party Advisory |
| https://github.com/BetterErrors/better_errors/pull/474 | Patch Third Party Advisory |
| https://github.com/BetterErrors/better_errors/security/advisories/GHSA-w3j4-76qw-wwjm | Third Party Advisory |
| https://github.com/BetterErrors/better_errors/commit/8e8e796bfbde4aa088741823c8a3fc6df2089bb0 | Patch Third Party Advisory |
| https://github.com/BetterErrors/better_errors/discussions/507 | Third Party Advisory |
| https://github.com/BetterErrors/better_errors/pull/474 | Patch Third Party Advisory |
| https://github.com/BetterErrors/better_errors/security/advisories/GHSA-w3j4-76qw-wwjm | 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-2021-39197 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-39197 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.
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CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://github.com/BetterErrors/better_errors/commit/8e8e796bfbde4aa088741823c8a3fc6df2089bb0 Added Reference https://github.com/BetterErrors/better_errors/discussions/507 Added Reference https://github.com/BetterErrors/better_errors/pull/474 Added Reference https://github.com/BetterErrors/better_errors/security/advisories/GHSA-w3j4-76qw-wwjm -
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Initial Analysis by [email protected]
Sep. 14, 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:P/I:P/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Changed Reference Type https://github.com/BetterErrors/better_errors/commit/8e8e796bfbde4aa088741823c8a3fc6df2089bb0 No Types Assigned https://github.com/BetterErrors/better_errors/commit/8e8e796bfbde4aa088741823c8a3fc6df2089bb0 Patch, Third Party Advisory Changed Reference Type https://github.com/BetterErrors/better_errors/discussions/507 No Types Assigned https://github.com/BetterErrors/better_errors/discussions/507 Third Party Advisory Changed Reference Type https://github.com/BetterErrors/better_errors/pull/474 No Types Assigned https://github.com/BetterErrors/better_errors/pull/474 Patch, Third Party Advisory Changed Reference Type https://github.com/BetterErrors/better_errors/security/advisories/GHSA-w3j4-76qw-wwjm No Types Assigned https://github.com/BetterErrors/better_errors/security/advisories/GHSA-w3j4-76qw-wwjm Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:better_errors_project:better_errors:*:*:*:*:*:ruby:*:* versions up to (excluding) 2.8.0
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-39197 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-2021-39197
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.21 }} 0.05%
score
0.40859
percentile