CVE-2026-59828

Medium

Description

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, post revisions that should be hidden from regular users could be leaked through visible diffs on adjacent revisions serialized by PostRevisionSerializer. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

SeverityMedium
CVSS5.3
Exploit probability—
ProductDiscourse
PublishedJul 9, 2026
First seenJul 9, 2026

How to fix

Update
  • discourse discourse2026.1.5, 2026.4.2, 2026.5.1 or later

Affected products

ProductAffected versionsFixed in
discourse discourse2026.1.0 ≤ v < 2026.1.5, 2026.4.0 ≤ v < 2026.4.2, 2026.5.0 ≤ v < 2026.5.1, 2026.6.02026.1.5, 2026.4.2, 2026.5.1

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