CVE-2026-55491

mediumpriority · track · 0EPSS 0.003 · 21 %ileDE
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.29% (21st) EPSS
CVSS 5.4 · medium
Is it mine?
2 products
Check your exposure
Who says so?
1 sources
cert_bund

EPSS · scored 2026-10-28

BigBlueButton is an open-source virtual classroom. Prior to 3.0.29, BigBlueButton failed to escape meetingName in record-and-playback/screenshare/playback/index.html.erb when generating the screenshare playback format. A low-privileged user could store a crafted meeting name that embedded script content, and the script executed in another user's browser when that user replayed the recording. This issue is fixed in version 3.0.29.

01

cvss

Technical severity, 0–10. One row per scoring source.

5.4
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · security-advisories@github.comexploitability 2.3 · impact 2.7
v3.15mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79US
04

affected products (2)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-1916BigBlueButton: Mehrere SchwachstellenDeutsch2026-06-14csaf · cert_bundDE

    Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in BigBlueButton ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen, Sicherheitsmaßnahmen zu umgehen und Daten zu manipulieren.

06

sources

Which sources assert this record, and when.

cert_bundNVDCVE.orgMITRE
published 2026-08-20modified 2026-10-26
07

references (3) nvd

External citations — patches, advisories, analysis.

scry

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