Read the docs
TI-2026-25812 Aliases CVE-2026-33415

Discourse: Improper Access Control in discourse-ai Allows Unauthorized Category Content Exposure

Priority LOW 23CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-284.

Summary

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.3, 2026.2.0-latest to before 2026.2.2, and 2026.3.0-latest to before 2026.3.0, an authenticated moderator-level user could retrieve post content, topic titles, and usernames from categories they were not authorized to view. Insufficient access controls on a sentiment analytics endpoint allowed category permission boundaries to be bypassed. This issue has been patched in versions 2026.1.3, 2026.2.2, and 2026.3.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00196 9th percentileScored 2026-11-07
Fix Fixed discourse (discourse): 2026.1.3, 2026.2.2, 2026.3.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
discoursediscourse2026.1.0-latest to before 2026.1.3; 2026.2.0-latest to before 2026.2.2; 2026.3.0-latest to before 2026.3.02026.1.3, 2026.2.2, 2026.3.0Patch availableCNA
  • discourse Vendordiscourse Affected 2026.1.0-latest to before 2026.1.3; 2026.2.0-latest to before 2026.2.2; 2026.3.0-latest to before 2026.3.0 Fixed in 2026.1.3, 2026.2.2, 2026.3.0 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:latest:*:*:*2026.1.0 to before 2026.1.3; 2026.2.0 to before 2026.2.2Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:*2026.3.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest.1:*:*:*2026.3.0Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:latest:*:*:* Versions 2026.1.0 to before 2026.1.3; 2026.2.0 to before 2026.2.2 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:* Versions 2026.3.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest.1:*:*:* Versions 2026.3.0 Vulnerable ·discourse

Remediation

  • Fix · CNA discourse (discourse) Fixed in 2026.1.3, 2026.2.2, 2026.3.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33415

References

Patch 1

Advisory 1

  • TI-2021-19656 Denial of Service in discourse CVSS 3.1MEDIUM 6.8
  • TI-2024-36150 Potential Backup file leaked via Nginx in Discourse CVSS 3.1HIGH 7.5
  • TI-2021-18002 RCE via malicious SNS subscription payload CVSS 3.1CRITICAL 10.0
  • TI-2026-24651 Discourse: Open redirect via `sso_destination_url` cookie in `enter` CVSS 4.0MEDIUM 5.1
  • TI-2026-22278 Discourse leaks private topic title and post excerpt via user action API endpoint CVSS 4.0HIGH 8.7
  • TI-2023-24152 Unauthenticated access to new private chat messages in Discourse CVSS 3.1HIGH 7.5
See all 262 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences