CVE-2026-27736

BigBlueButton has Open Redirect vulnerability in ApiController

Published: Feb 25, 2026Updated: Mar 5, 2026 Sources: CVE List NVDCWE-601

6.1MEDIUM

Description

BigBlueButton is an open-source virtual classroom. In versions on the 3.x branch prior to 3.0.20, the string received with errorRedirectUrl lacks validation, using it directly in the respondWithRedirect function leads to an Open Redirect vulnerability. BigBlueButton 3.0.20 patches the issue. No known workarounds are available.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:LConfidentiality

Low

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-601

Affected Products

bigbluebutton

oss-projectaka bbb

bigbluebuttonOn-premWeb App

Communications / video-conferencing

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/bigbluebutton/bigbluebutton/commit/691f92f3af0d6b796b91cb968977068663119812

github.com

https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-65cv-rg9f-qqrx

github.com

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