Discourse post diff leakage before 2026.6.0 (CVE-2026-59828)
CVE-2026-59828 Published on July 9, 2026
Discourse: Hidden post revisions leak through adjacent visible diffs
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.
Vulnerability Analysis
CVE-2026-59828 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity and availability.
Weakness Type
What is an Information Disclosure Vulnerability?
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CVE-2026-59828 has been classified to as an Information Disclosure vulnerability or weakness.
Products Associated with CVE-2026-59828
Want to know whenever a new CVE is published for Discourse? stack.watch will email you.
Affected Versions
discourse:- Version >= 2026.1.0-latest, < 2026.1.5 is affected.
- Version >= 2026.4.0-latest, < 2026.4.2 is affected.
- Version >= 2026.5.0-latest, < 2026.5.1 is affected.