9.8
CRITICAL CVSS 3.1
CVE-2020-12443
BigBlueButton Directory Traversal File Read
Description

BigBlueButton before 2.2.6 allows remote attackers to read arbitrary files because the presfilename (lowercase) value can be a .pdf filename while the presFilename (mixed case) value has a ../ sequence. This can be leveraged for privilege escalation via a directory traversal to bigbluebutton.properties. NOTE: this issue exists because of an ineffective mitigation to CVE-2020-12112 in which there was an attempted fix within an NGINX configuration file, without considering that the relevant part of NGINX is case-insensitive.

INFO

Published Date :

April 29, 2020, 2:15 a.m.

Last Modified :

Nov. 21, 2024, 4:59 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2020-12443 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Bigbluebutton bigbluebutton
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 HIGH [email protected]
CVSS 3.1 CRITICAL [email protected]
Public PoC/Exploit Available at Github

CVE-2020-12443 has a 1 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

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-2020-12443.

URL Resource
https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463 Patch Third Party Advisory
https://github.com/mclab-hbrs/BBB-POC Exploit Third Party Advisory
https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463 Patch Third Party Advisory
https://github.com/mclab-hbrs/BBB-POC Exploit Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2020-12443 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-2020-12443 weaknesses.

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).

Profile Photo
mclab-hbrs/BBB-POC

Proof Of Concept Exploits For BBB

Shell

Updated: 5 years, 3 months ago
0 stars 1 fork 1 watcher
Born at : April 28, 2020, 5:06 p.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2020-12443 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2020-12443 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 af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463
    Added Reference https://github.com/mclab-hbrs/BBB-POC
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    May. 06, 2020

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463 No Types Assigned https://github.com/bigbluebutton/bigbluebutton/pull/9259/commits/b21ca8355a57286a1e6df96984b3a4c57679a463 Patch, Third Party Advisory
    Changed Reference Type https://github.com/mclab-hbrs/BBB-POC No Types Assigned https://github.com/mclab-hbrs/BBB-POC Exploit, Third Party Advisory
    Added CWE NIST CWE-22
    Added CPE Configuration OR *cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* versions up to (excluding) 2.2.6
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 7.5
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.85 }} 0.24%

score

0.73898

percentile