BigBlueButton Unrestricted File Upload vulnerability
Priority LOW 39CWE-434Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-434.
Summary
BigBlueButton is an open-source virtual classroom. BigBlueButton prior to version 2.6.0-beta.2 is vulnerable to unrestricted file upload, where the insertDocument API call does not validate the given file extension before saving the file, and does not remove it in case of validation failures. BigBlueButton 2.6.0-beta.2 contains a patch. There are no known workarounds.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00659 51st percentileScored 2026-11-07
Fix Fixed bigbluebutton (bigbluebutton): 2.6.0-beta.2
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 2.6.0-beta.2 | 2.6.0-beta.2 | Patch available | CNA |
- bigbluebutton Vendorbigbluebutton Affected before 2.6.0-beta.2 Fixed in 2.6.0-beta.2 Patch available CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* | up to 2.5.18 | Vulnerable | bigbluebutton |
| cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha1:*:*:*:*:*:* | 2.6.0 alpha1 | Vulnerable | bigbluebutton |
| cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha2:*:*:*:*:*:* | 2.6.0 alpha2 | Vulnerable | bigbluebutton |
| cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha3:*:*:*:*:*:* | 2.6.0 alpha3 | Vulnerable | bigbluebutton |
| cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha4:*:*:*:*:*:* | 2.6.0 alpha4 | Vulnerable | bigbluebutton |
| cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:beta1:*:*:*:*:*:* | 2.6.0 beta1 | Vulnerable | bigbluebutton |
- cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:* Versions up to 2.5.18 Vulnerable ·bigbluebutton
- cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha1:*:*:*:*:*:* Versions 2.6.0 alpha1 Vulnerable ·bigbluebutton
- cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha2:*:*:*:*:*:* Versions 2.6.0 alpha2 Vulnerable ·bigbluebutton
- cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha3:*:*:*:*:*:* Versions 2.6.0 alpha3 Vulnerable ·bigbluebutton
- cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:alpha4:*:*:*:*:*:* Versions 2.6.0 alpha4 Vulnerable ·bigbluebutton
- cpe:2.3:a:bigbluebutton:bigbluebutton:2.6.0:beta1:*:*:*:*:*:* Versions 2.6.0 beta1 Vulnerable ·bigbluebutton
Remediation
- Fix · CNA bigbluebutton (bigbluebutton) Fixed in 2.6.0-beta.2
Timeline
- 2026-10-02 Threatist record created from CVE-2023-42803
- 2026-10-31 EPSS moved to the 50th–90th percentile
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
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences