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TI-2023-12691 Aliases CVE-2023-28112

Discourse's SSRF protection missing for some FastImage requests

Priority LOW 36CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, some user provided URLs were being passed to FastImage without SSRF protection. Insufficient protections could enable attackers to trigger outbound network connections from the Discourse server to private IP addresses. This affects any site running the `tests-passed` or `beta` branches versions 3.1.0.beta2 and prior. This issue is patched in version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00583 48th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

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
discoursediscoursebeta < 3.1.0.beta3; tests-passed < 3.1.0.beta3—No fix listedCNA
  • discourse Vendordiscourse Affected beta < 3.1.0.beta3; tests-passed < 3.1.0.beta3 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:*before 3.1.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:*up to 3.1.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:*3.1.0 beta1Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:*3.1.0 beta2Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* Versions before 3.1.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:* Versions up to 3.1.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:* Versions 3.1.0 beta1 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:* Versions 3.1.0 beta2 Vulnerable ·discourse

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-28112

References

Patch 2

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