Discourse
CVE-2026-33410
MEDIUM
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Lifecycle Timeline
2DescriptionGitHub Advisory
Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have two authorization issues in the chat direct message API. First, when creating a direct message channel or adding users to an existing one, the target_groups parameter was passed directly to the user resolution query without checking group or member visibility for the acting user. An authenticated chat user could craft an API request with a known private/hidden group name and receive a channel containing that group's members, leaking their identities. Second, can_chat? only checked group membership, not the chat_enabled user preference. A chat-disabled user could create or query DM channels between other users via the direct messages API, potentially exposing private last_message content from the serialized channel response. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.
AnalysisAI
A remote code execution vulnerability in Discourse (CVSS 5.4). Remediation should follow standard vulnerability management procedures.
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Vulnerability AssessmentAI
| Risk Assessment | CVSS 5.4. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker could exploit this vulnerability in Discourse to compromise the security of affected deployments, potentially impacting confidentiality, integrity, or availability. |
| Remediation | Monitor vendor channels for patch availability. Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
More from same product – last 7 days
Information disclosure in Discourse discussion platform allows any MessageBus subscriber to receive real-time chat messa
Path traversal in Discourse's backup download handler allows an authenticated administrator on one site within a multisi
Discourse group owners can retrieve plaintext SMTP credentials - including passwords, usernames, server, port, and SSL m
Whisper channel access control in Discourse can be bypassed by any authenticated forum user, allowing injection of conte
Discourse chat plugin across versions 2026.1.0-2026.4.x contains four authorization deficiencies (CWE-862) enabling both
Share
External POC / Exploit Code
Leaving vuln.today