BigBlueButton has Stored XSS in bbb-playback replay_CVE-2026-27737

6.5 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Description

BigBlueButton is an open-source virtual classroom. In versions prior to 3.0.19, the recording playback (presentation format) was not sanitizing user's input in public chat. This allowed for a malicious actor to craft and carry out a targeted XSS attack, activated on anyone replaying the recording. This issue has been fixed 3.0.19.

Basic Information

ID CVE-2026-27737

Source GitHub_M

Published May 18, 2026 at 21:11

Affected Product

Vendor bigbluebutton

Product bigbluebutton

Version < 3.0.19

Affected Versions bigbluebutton bigbluebutton < 3.0.19
blindsidenetworks scalite < 1.7.0
bigbluebutton bbb-playback < 5.4.3

CWE Classification

CWE-79

References

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    "published": "2026-05-18T21:11:17.611Z",
    "modified": "2026-05-18T21:11:17.611Z",
    "type": "cve",
    "title": "BigBlueButton has Stored XSS in bbb-playback replay",
    "source": "GitHub_M",
    "references": "https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-8vv7-vj94-q2pv\nhttps://github.com/bigbluebutton/bbb-playback/commit/09e89bfe4ff8488b68c3ff040d3081e419dc89b1\nhttps://github.com/bigbluebutton/bigbluebutton/commit/69f45aa1b963dc7d80179d0155acc670aec5c4fc\nhttps://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.19\nhttps://github.com/blindsidenetworks/scalelite/releases/tag/v1.7.0",
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