Cyber Resilience

CVE-2023-45131

High

Published: 16 October 2023

Published
16 October 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0739 91.9th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-45131 is a high-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Discourse Discourse. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 8.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

Discourse, an open source discussion platform, contains an information disclosure vulnerability in its chat subsystem. Unauthenticated attackers can retrieve new chat messages by issuing a POST request to the MessageBus endpoint, exposing message contents that should require authentication. The flaw is tracked as CWE-200 and carries a CVSS 3.1 score of 7.5 reflecting network attack vector, low complexity, and high confidentiality impact. It affects versions prior to the 3.1.1 stable and 3.2.0.beta2 releases.

Any remote attacker without credentials can exploit the issue to read newly posted chat messages, potentially accessing private or sensitive discussion content. Because the request is unauthenticated and requires no user interaction, the exposure applies to any Discourse instance with chat enabled and reachable over the network.

The official GitHub Security Advisory recommends immediate upgrade to the patched releases and states that no workarounds are available. The associated EPSS scores have remained low, with a current value of 0.0739 and a peak of 0.0838.

EU & UK References

Vulnerability details

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…

more

upgrade. There are no known workarounds for this vulnerability.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

discourse
discourse
3.2.0 · ≤ 3.1.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-200

Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.

addresses: CWE-200

Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.

addresses: CWE-200

Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.

addresses: CWE-200

By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.

addresses: CWE-200

Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.

addresses: CWE-200

Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.

addresses: CWE-200

Literacy training teaches users to recognize and avoid actions that result in unauthorized exposure of sensitive information.

addresses: CWE-200

Retaining and monitoring training records confirms personnel have completed privacy and security awareness training on handling sensitive data, reducing the chance of unauthorized exposure due to lack of knowledge.

References