Discourse up to 2026.1.1/2026.2.0/2026.3.0-latest API Endpoint authorization

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in Discourse up to 2026.1.1/2026.2.0/2026.3.0-latest and classified as problematic. Affected by this issue is some unknown functionality of the component API Endpoint. The manipulation leads to authorization. This vulnerability is referenced as CVE-2026-27491. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Discourse up to 2026.1.1/2026.2.0/2026.3.0-latest. It has been rated as problematic. This issue affects an unknown part of the component API Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-27491 since 02/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 2026.1.2 or 2026.2.1 eliminates this vulnerability. Applying the patch 60a588f4da4ab0feceb2c44787d4261b4f8757be is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 4.3
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Discourse 2026.1.2/2026.2.1
Patch: 60a588f4da4ab0feceb2c44787d4261b4f8757be

Timelineinfo

02/19/2026 CVE reserved
03/20/2026 +29 days Advisory disclosed
03/20/2026 +0 days VulDB entry created
03/25/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-xq37-5fvf-4m4j
Status: Confirmed

CVE: CVE-2026-27491 (🔒)
GCVE (CVE): GCVE-0-2026-27491
GCVE (VulDB): GCVE-100-351935

Entryinfo

Created: 03/20/2026 08:11
Updated: 03/25/2026 04:03
Changes: 03/20/2026 08:11 (69), 03/24/2026 08:57 (1), 03/25/2026 04:03 (10)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

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