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TI-2026-25613 Aliases CVE-2026-33185

Discourse: Group SMTP test endpoint susceptible to SSRF

Priority LOW 29CWE-918Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-918 and the CVSS impact.

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, the group email settings test endpoint could be used to make the server initiate outbound connections to arbitrary hosts and ports. This could allow probing of internal network infrastructure. The endpoint was accessible to non-staff group owners. 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 0.00198 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
Yes
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-2026-33185

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