What is the CVSS score of CVE-2026-27491?

CVE-2026-27491 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Discourse are affected by CVE-2026-27491?

Organizations using Discourse should be aware of moderate risk from CVE-2026-27491, a missing authorization vulnerability rated CVSS 4.3. Attackers could gain access beyond their authorized level.. A patch is available.

How to fix or mitigate CVE-2026-27491?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Discourse CVE-2026-27491

EUVD-2026-13190 MEDIUM

Missing Authorization (CWE-862)

2026-03-19 GitHub_M

Authentication Bypass Privilege Escalation Information Disclosure Discourse

4.3

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

4.3 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Lifecycle Timeline

Patch available

Apr 16, 2026 - 05:29 EUVD

2026.1.2,2026.2.1

EUVD ID Assigned

Mar 19, 2026 - 21:00 euvd

EUVD-2026-13190

Analysis Generated

Mar 19, 2026 - 21:00 vuln.today

CVE Published

Mar 19, 2026 - 20:47 nvd

MEDIUM 4.3

DescriptionGitHub Advisory

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, a type coercion issue in a post actions API endpoint allowed non-staff users to issue warnings to other users. Warnings are a staff-only moderation feature. The vulnerability required the attacker to be a logged-in user and to send a specifically crafted request. No data exposure or privilege escalation beyond the ability to create unauthorized user warnings was possible. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.

AnalysisAI

Unauthorized user warnings in Discourse prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 can be issued by authenticated non-staff users due to a type coercion flaw in the post actions API endpoint. Attackers with valid login credentials can exploit this to send warnings meant only for staff moderators, though no data exposure or further privilege escalation occurs. No patch workaround is currently available.

Technical ContextAI

Privilege escalation allows a low-privileged user or process to gain elevated permissions beyond what was originally authorized. This vulnerability is classified as Missing Authorization (CWE-862).

RemediationAI

Apply the principle of least privilege. Keep systems patched. Monitor for suspicious privilege changes. Use mandatory access controls (SELinux, AppArmor).