Information Disclosure in Discourse Open-Source Discussion Platform
CVE-2026-59828

5.3MEDIUM

Key Information:

Vendor

Discourse
Status
Discourse
Vendor
CVE Published:
9 July 2026

What is CVE-2026-59828?

The Discourse open-source discussion platform has a vulnerability where post revisions intended to be hidden from standard users could inadvertently be exposed. This occurs through visible diffs in adjacent revisions that are serialized by the PostRevisionSerializer. This leakage permits the unauthorized viewing of certain content revisions prior to the fixes implemented in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5. Users of these affected versions are strongly advised to update to the latest releases to mitigate this security risk.

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/1f26c1163ce...
x_refsource_MISC
https://github.com/discourse/discourse/commit/8b773332b0f...
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

.