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TI-2023-25460 Aliases CVE-2023-47120

Discourse DoS through Onebox favicon URL

Priority MEDIUM 41CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

Discourse is an open source platform for community discussion. In versions 3.1.0 through 3.1.2 of the `stable` branch and versions 3.1.0,beta6 through 3.2.0.beta2 of the `beta` and `tests-passed` branches, Redis memory can be depleted by crafting a site with an abnormally long favicon URL and drafting multiple posts which Onebox it. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.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 0.00982 62nd percentileScored 2026-11-07
Fix Fixed discourse (discourse): 3.1.3, 3.2.0.beta3

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
discoursediscourse3.1.0 to before 3.1.3; 3.1.0.beta6 to before 3.2.0.beta33.1.3, 3.2.0.beta3Patch availableCNA
  • discourse Vendordiscourse Affected 3.1.0 to before 3.1.3; 3.1.0.beta6 to before 3.2.0.beta3 Fixed in 3.1.3, 3.2.0.beta3 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:*3.1.0 to before 3.1.3Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta6:*:*:beta:*:*:*3.1.0 beta6Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta7:*:*:beta:*:*:*3.1.0 beta7Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.1.0:beta8:*:*:beta:*:*:*3.1.0 beta8Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.2.0:beta1:*:*:beta:*:*:*3.2.0 beta1Vulnerablediscourse
cpe:2.3:a:discourse:discourse:3.2.0:beta2:*:*:beta:*:*:*3.2.0 beta2Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:* Versions 3.1.0 to before 3.1.3 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta6:*:*:beta:*:*:* Versions 3.1.0 beta6 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta7:*:*:beta:*:*:* Versions 3.1.0 beta7 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.1.0:beta8:*:*:beta:*:*:* Versions 3.1.0 beta8 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.2.0:beta1:*:*:beta:*:*:* Versions 3.2.0 beta1 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:3.2.0:beta2:*:*:beta:*:*:* Versions 3.2.0 beta2 Vulnerable ·discourse

Remediation

  • Fix · CNA discourse (discourse) Fixed in 3.1.3, 3.2.0.beta3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-47120

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