{"api_version":"1","generated_at":"2026-09-11T01:02:38+00:00","cve":"CVE-2026-55491","urls":{"html":"https://cve.report/CVE-2026-55491","api":"https://cve.report/api/cve/CVE-2026-55491.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55491","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55491"},"summary":{"title":"BigBlueButton: Stored XSS in Screenshare Recording Playback via Unescaped Meeting Name","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-08-20 22:17:22","updated_at":"2026-08-21 16:17:19"},"problem_types":["CWE-79","CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"5.4","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","baseScore":5.4,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"5.4","severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.4,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"references":[{"url":"https://github.com/bigbluebutton/bigbluebutton/commit/a53f2b92022388bfa4109d3136d1f3a932404b1b","name":"https://github.com/bigbluebutton/bigbluebutton/commit/a53f2b92022388bfa4109d3136d1f3a932404b1b","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-57p5-c888-74f9","name":"https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-57p5-c888-74f9","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.29","name":"https://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.29","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-55491","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55491","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"bigbluebutton","product":"bigbluebutton","version":"affected < 3.0.29","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"55491","cve":"CVE-2026-55491","epss":"0.001650000","percentile":"0.059470000","score_date":"2026-08-24","updated_at":"2026-08-25 00:11:33"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-55491","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-08-21T15:49:35.408716Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-08-21T15:50:11.735Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"product":"bigbluebutton","vendor":"bigbluebutton","versions":[{"status":"affected","version":"< 3.0.29"}]}],"descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":5.4,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-08-20T21:35:42.546Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-57p5-c888-74f9","tags":["x_refsource_CONFIRM"],"url":"https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-57p5-c888-74f9"},{"name":"https://github.com/bigbluebutton/bigbluebutton/commit/a53f2b92022388bfa4109d3136d1f3a932404b1b","tags":["x_refsource_MISC"],"url":"https://github.com/bigbluebutton/bigbluebutton/commit/a53f2b92022388bfa4109d3136d1f3a932404b1b"},{"name":"https://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.29","tags":["x_refsource_MISC"],"url":"https://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.29"}],"source":{"advisory":"GHSA-57p5-c888-74f9","discovery":"UNKNOWN"},"title":"BigBlueButton: Stored XSS in Screenshare Recording Playback via Unescaped Meeting Name"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-55491","datePublished":"2026-08-20T21:35:42.546Z","dateReserved":"2026-06-16T22:28:27.062Z","dateUpdated":"2026-08-21T15:50:11.735Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-20 22:17:22","lastModifiedDate":"2026-08-21 16:17:19","problem_types":["CWE-79","CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","baseScore":5.4,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.3,"impactScore":2.7}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-08-21T15:49:35.408716Z","id":"CVE-2026-55491","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"55491","Ordinal":"1","Title":"BigBlueButton: Stored XSS in Screenshare Recording Playback via ","CVE":"CVE-2026-55491","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"55491","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"BigBlueButton: Stored XSS in Screenshare Recording Playback via "}]}}}