Medium severity · published Oct 30, 2023
CVE-2023-42804
BigBlueButton Path Traversal – Reading Certain File Extensions
5.3
CVSS
0.5%
EPSS
No
On KEV
Description
BigBlueButton is an open-source virtual classroom. BigBlueButton prior to version 2.6.0-beta.1 has a path traversal vulnerability that allows an attacker with a valid starting folder path, to traverse and read other files without authentication, assuming the files have certain extensions (txt, swf, svg, png). In version 2.6.0-beta.1, input validation was added on the parameters being passed and dangerous characters are stripped. There are no known workarounds.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BI
bigbluebutton · bigbluebutton
< 2.6.0-beta.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-42804
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-42804
Third Party Advisory
https://github.com/bigbluebutton/bigbluebutton/pull/15960
Third Party Advisory
https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-3qjg-229m-vq84
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