TI-2025-34876 Aliases CVE-2025-55200

BigBlueButton vulnerable to Stored XSS via name of user at Shared Notes

LOW 31CWE-79Published 2025-10-09 · Updated 2025-10-09

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Cross-site scripting
Confidentiality · integrity · availability: High · Low · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

BigBlueButton is an open-source virtual classroom. In versions prior to 3.0.13, the "Shared Notes" feature contains a Stored Cross-Site Scripting (XSS) vulnerability with the input location being the "Username" field and the output location on the "Shared Notes" page, when a user with a malicious username is editing content. This vulnerability allows a low-privileged user to execute arbitrary JavaScript in the context of higher-privileged users (e.g., Admins) who open the Shared Notes page. Version 3.0.13 fixes the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00249 16th percentileScored 2026-11-07

Fix Fixed bigbluebutton (bigbluebutton): 3.0.13

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
bigbluebutton	bigbluebutton	before 3.0.13	3.0.13	Patch available	CNA

bigbluebutton Vendorbigbluebutton Affected before 3.0.13 Fixed in 3.0.13 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:bigbluebutton:bigbluebutton::::::::	before 3.0.13	Vulnerable	bigbluebutton

cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* Versions before 3.0.13 Vulnerable ·bigbluebutton

Remediation

Fix · CNA bigbluebutton (bigbluebutton) Fixed in 3.0.13

Timeline

2026-10-02 Threatist record created from CVE-2025-55200

References

Patch 1

https://github.com/bigbluebutton/bigbluebutton/pull/23693

Advisory 1

https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-9jv9-cjrm-grj2

Other 2

TI-2026-21873 BigBlueButton: Exposed ClamAV port enables Denial of Service CVSS 3.1HIGH 8.2
TI-2025-38047 BigBlueButton vulnerable to Chat DoS via invalid reactionEmojiId CVSS 3.1HIGH 7.5
TI-2025-38046 BigBlueButton vulnerable to DoS via PollSubmitVote GraphQL mutation CVSS 3.1HIGH 7.5
TI-2022-13109 Cross site scripting in username that will trigger by sending chat CVSS 3.1MEDIUM 6.5
TI-2020-09954 BigBlueButton before 2.2.6 allows remote attackers to read arbitrary files because the… CVSS 3.1CRITICAL 9.8
TI-2020-16722 BigBlueButton through 2.2.28 uses Ghostscript for processing of uploaded EPS documents… CVSS 3.1CRITICAL 9.8

See all 48 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences