CVE-2020-12443: Path Traversal
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.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the vulnerability ID for this issue?
The vulnerability ID for this issue is CVE-2020-12443.
What is the severity of CVE-2020-12443?
The severity of CVE-2020-12443 is critical, with a severity value of 9.8.
What software versions are affected by CVE-2020-12443?
BigBlueButton versions up to 2.2.6 are affected by CVE-2020-12443.
How can remote attackers exploit CVE-2020-12443?
Remote attackers can exploit CVE-2020-12443 by leveraging a directory traversal vulnerability to read arbitrary files.
Are there any fixes or patches available for CVE-2020-12443?
Yes, a fix is available in BigBlueButton version 2.2.6. It is recommended to update to this version to mitigate the vulnerability.