Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Lifecycle Timeline
4DescriptionGitHub Advisory
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, requesting /posts/:id.json?version=X bypassed authorization checks on post revisions. The display_post method called post.revert_to directly without verifying whether the revision was hidden or if the user had permission to view edit history. This meant hidden revisions (intentionally concealed by staff) could be read by any user by simply enumerating version numbers. Starting in versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, Discourse looks up the PostRevision and call guardian.ensure_can_see! before reverting, consistent with how the /posts/:id/revisions/:revision endpoint already authorizes access. No known workarounds are available.
AnalysisAI
Unauthorized access to hidden post revisions in Discourse through version enumeration allows unauthenticated users to bypass authorization checks and read staff-concealed edit history. The /posts/:id.json endpoint fails to validate user permissions before displaying revision content, enabling attackers to enumerate version numbers and access sensitive historical data. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Vulnerability AssessmentAI
| Risk Assessment | CVSS score of 5.3 (MEDIUM). Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Remediation | Monitor vendor advisories for patches. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
More from same product – last 7 days
Information disclosure in Discourse discussion platform allows any MessageBus subscriber to receive real-time chat messa
Path traversal in Discourse's backup download handler allows an authenticated administrator on one site within a multisi
Discourse group owners can retrieve plaintext SMTP credentials - including passwords, usernames, server, port, and SSL m
Whisper channel access control in Discourse can be bypassed by any authenticated forum user, allowing injection of conte
Discourse chat plugin across versions 2026.1.0-2026.4.x contains four authorization deficiencies (CWE-862) enabling both
Share
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-13188