BigBlueButton vulnerable to Chat DoS via invalid reactionEmojiId

Description

BigBlueButton is an open-source virtual classroom. A denial-of-service (DoS) vulnerability in versions prior to 3.0.13 allows any authenticated user to crash the chat functionality for all participants in a meeting by sending a malformed `reactionEmojiId` in the GraphQL mutation `chatSendMessageReaction`. Version 3.0.13 contains a patch. No known workarounds are available.

Scores

EPSS (exploitation in 30 days)

0.39% · top 66% of all CVEs (5 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

• CWE-703: Improper Check or Handling of Exceptional Conditions (opens in a new tab)All about CWE-703 and its CVEs

Affected products

• bigbluebutton · bigbluebutton

  • affected < 3.0.13

References (2)

• https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-45j2-m26c-3pcm (opens in a new tab)x_refsource_CONFIRMexploit
• https://github.com/bigbluebutton/bigbluebutton/pull/23651 (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2025-61602](https://trackcve.app/badge/CVE-2025-61602.svg)](https://trackcve.app/cve/CVE-2025-61602)

Record last updated 10 Oct 2025, 14:30 UTC.