CVE-2020-12443

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.

CVSS v3 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	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

Configurations

Configuration 1 (hide)

cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2020-04-29 02:15

Updated : 2023-12-10 13:27

NVD link : CVE-2020-12443

Mitre link : CVE-2020-12443

CVE.ORG link : CVE-2020-12443

JSON object : View

Products Affected

bigbluebutton

bigbluebutton

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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