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TI-2025-39918 Aliases CVE-2025-64528

Users are able to find users by name even when `enable_names` is off

Priority LOW 28CWE-202Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Discourse is an open source discussion platform. Prior to versions 3.5.3, 2025.11.1, and 2025.12.0, an attacker who knows part of a username can find the user and their full name via UI or API, even when `enable_names` is disabled. Versions 3.5.3, 2025.11.1, and 2025.12.0 contain a fix.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00287 21st percentileScored 2026-11-07
Fix Fixed discourse (discourse): 3.5.3, 2025.11.1, 2025.12.0

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
discoursediscoursebefore 3.5.3; 2025.11.0-latest to before 2025.11.1; 2025.12.0-latest to before 2025.12.03.5.3, 2025.11.1, 2025.12.0Patch availableCNA
  • discourse Vendordiscourse Affected before 3.5.3; 2025.11.0-latest to before 2025.11.1; 2025.12.0-latest to before 2025.12.0 Fixed in 3.5.3, 2025.11.1, 2025.12.0 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*before 3.5.3Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2025.11.0:*:*:*:stable:*:*:*2025.11.0Vulnerablediscourse
cpe:2.3:a:discourse:discourse:2025.12.0:*:*:*:stable:*:*:*2025.12.0Vulnerablediscourse
  • cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* Versions before 3.5.3 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2025.11.0:*:*:*:stable:*:*:* Versions 2025.11.0 Vulnerable ·discourse
  • cpe:2.3:a:discourse:discourse:2025.12.0:*:*:*:stable:*:*:* Versions 2025.12.0 Vulnerable ·discourse

Remediation

  • Fix · CNA discourse (discourse) Fixed in 3.5.3, 2025.11.1, 2025.12.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-64528

References

Patch 3

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