CVE-2025-68659

Summary

Discourse is an open source discussion platform. Versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 have an application level denial of service vulnerabilityin the username change functionality at try.discourse.org. The vulnerability allows attackers to cause noticeable server delays and resource exhaustion by sending large JSON payloads to the username preference endpoint PUT /u//preferences/username, resulting in degraded performance for other users and endpoints. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.

Affected Software

VendorProductVersion RangeStatus
discoursediscourse< 3.5.4affected
discoursediscourse>= 2025.11.0-latest, < 2025.11.2affected
discoursediscourse>= 2025.12.0-latest, < 2025.12.1affected
discoursediscourse>= 2026.1.0-latest, < 2026.1.0affected

Weaknesses

  • CWE-770: CWE-770: Allocation of Resources Without Limits or Throttling

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References