Vulnerability Database

309,136

Total vulnerabilities in the database

CVE-2021-30477

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of replies to messages sent by outgoing webhooks to private streams meant that an outgoing webhook bot could be used to send messages to private streams that the user was not intended to be able to send messages to.

  • Published: Apr 15, 2021
  • Updated: Nov 16, 2025
  • CVE: CVE-2021-30477
  • Severity: Low
  • Exploit:

CVSS v3:

  • Severity: Low
  • Score: 4.3
  • AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CVSS v2:

  • Severity: Low
  • Score: 4
  • AV:N/AC:L/Au:S/C:N/I:P/A:N

No CWE or OWASP classifications available.

Software From Fixed in
zulip / zulip_server - 3.4