CVE-2023-45131

HIGH

Discourse < 3.1.1 - Unauthenticated Exposure of Sensitive Information via MessageBus

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2023-45131. PoCs published by İbrahimsql, ibrahmsql.

AI-analyzed exploit summary This Ruby script exploits CVE-2023-45131, an unauthenticated access vulnerability in Discourse's MessageBus, allowing enumeration of chat channels, interception of private messages, and real-time monitoring of communications. It demonstrates multiple attack vectors including channel enumeration and message history access.

Description

Discourse is an open source platform for community discussion. New chat messages can be read by making an unauthenticated POST request to MessageBus. This issue is patched in the 3.1.1 stable and 3.2.0.beta2 versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Exploits (2)

exploitdb WORKING POC
by İbrahimsql · rubywebappsmultiple
https://www.exploit-db.com/exploits/52375

This Ruby script exploits CVE-2023-45131, an unauthenticated access vulnerability in Discourse's MessageBus, allowing enumeration of chat channels, interception of private messages, and real-time monitoring of communications. It demonstrates multiple attack vectors including channel enumeration and message history access.

Classification
Working Poc 95%
Attack Type
Info Leak
Complexity
Moderate
Reliability
Reliable
Target: Discourse < 3.1.1 stable, < 3.2.0.beta2
No auth needed
Prerequisites: Network access to the target Discourse instance · MessageBus endpoint exposed
devstral-2 · analyzed Feb 16, 2026 Full analysis →
nomisec WORKING POC 3 stars
by ibrahmsql · poc
https://github.com/ibrahmsql/CVE-2023-45131

The repository contains a functional Ruby exploit for CVE-2023-45131, which allows unauthenticated access to private chat messages in Discourse via the MessageBus endpoint. The PoC demonstrates enumeration of chat channels, interception of private messages, and real-time monitoring.

Classification
Working Poc 95%
Attack Type
Auth Bypass
Complexity
Moderate
Reliability
Reliable
Target: Discourse < 3.1.1 stable, < 3.2.0.beta2
No auth needed
Prerequisites: Network access to the target Discourse instance · MessageBus endpoint exposed
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0739
EPSS Percentile 91.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-200
Status published
Products (2)
discourse/discourse 3.2.0 beta1
discourse/discourse < 3.1.1
Published Oct 16, 2023
Tracked Since Feb 18, 2026