Every CVE Search/ Get API key

CVE-2023-33176

Blind SSRF When Uploading Presentation in BigBlueButton

4.8 Medium

CVE-2023-33176 is a medium vulnerability (CVSS 4.8) in Bigbluebutton, published June 26, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.47%, the 40th percentile. No source names a fixed version.

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
High
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
Low
Integrity
None
Availability
Low

Exploit likelihood

0.47%Up 0.4 points since Jun 27, 2023
90%50%10%1%

What each source reports

CVE List Score used 4.8

Blind SSRF When Uploading Presentation in BigBlueButton

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

Record
CVE-2023-33176
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness
CWE-918
Updated
2026-11-02
EUVDEUVD-2023-37359 4.8

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

Record
EUVD-2023-37359
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Updated
2026-11-03
NVD 4.8

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

Record
CVE-2023-33176
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
CVSS 3.1
6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Weakness
CWE-918
Updated
2026-11-02
OSV 4.8

Blind SSRF When Uploading Presentation in BigBlueButton

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

Record
CVE-2023-33176
CVSS 3.1
4.8 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Weakness
CWE-918
Updated
2026-11-02

Affected products

History

History
WhenChangedSources
2026-11-03aliases, publishedEUVD
2026-11-02createdCVE List, NVD, OSV

References

MoveEnter Open