EventSerializer Vulnerability in Discourse Discussion Platform
CVE-2026-45780

5.3MEDIUM

Key Information:

Vendor

Discourse
Status
Discourse
Vendor
CVE Published:
9 July 2026

What is CVE-2026-45780?

An information disclosure issue in Discourse's EventSerializer could allow unauthorized users to access sensitive details about private events. Specifically, users who could view discussion topics might be able to see invited group names, sample invitees, and attendance statistics, which should be restricted. This vulnerability was addressed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, enhancing the security of the platform and safeguarding user privacy.

Affected Version(s)

discourse >= 2026.1.0-latest, < 2026.1.5 < 2026.1.0-latest, 2026.1.5

discourse >= 2026.4.0-latest, < 2026.4.2 < 2026.4.0-latest, 2026.4.2

discourse >= 2026.5.0-latest, < 2026.5.1 < 2026.5.0-latest, 2026.5.1

References

https://github.com/discourse/discourse/security/advisorie...
x_refsource_CONFIRM
https://github.com/discourse/discourse/commit/37969503f20...
x_refsource_MISC
https://github.com/discourse/discourse/commit/4d46638041b...
x_refsource_MISC

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.