In BigBlueButton before 2.2.28 (or earlier), uploaded presentations are sent to clients…
Priority LOW 29CWE-79Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-79.
Summary
In BigBlueButton before 2.2.28 (or earlier), uploaded presentations are sent to clients without a Content-Type header, which allows XSS, as demonstrated by a .png file extension for an HTML document.
Why it matters now
EPSS 0.00819 57th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* | before 2.2.28 | Vulnerable | bigbluebutton |
- cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* Versions before 2.2.28 Vulnerable ·bigbluebutton
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-27608
- 2026-10-03 Alias added: GHSA-43wq-r34m-56ch
References
More Bigbluebutton vulnerabilities
- 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
Sources
- CVE-2020-27608 · CVE Program
- CVE-2020-27608 · NVD
- FIRST EPSS
- GHSA-43wq-r34m-56ch · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences