# CVE-2026-26265: Discourse - Information Disclosure

> Live exploitation tracking for CVE-2026-26265 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2026-26265

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 7.5
- **Public exploit available:** Yes
- **Affected products:** Discourse
- **Weaknesses:** CWE-639 (Authorization Bypass Through User-Controlled Key)
- **Tags:** forum

## Description

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, an IDOR vulnerability in the directory items endpoint allows any user, including anonymous users, to retrieve private user field values for all users in the directory. The `user_field_ids` parameter in `DirectoryItemsController#index` accepts arbitrary user field IDs without authorization checks, bypassing the visibility restrictions (`show_on_profile` / `show_on_user_card`) that are enforced elsewhere (e.g., `UserCardSerializer` via `Guardian#allowed_user_field_ids`). An attacker can request `GET /directory_items.json?period=all&user_field_ids=<id>` with any private field ID and receive that field's value for every user in the directory response. This enables bulk exfiltration of private user data such as phone numbers, addresses, or other sensitive custom fields that admins have explicitly configured as non-public. The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by filtering `user_field_ids` against `UserField.public_fields` for non-staff users before building the custom field map. As a workaround, site administrators can remove sensitive data from private user fields, or disable the user directory via the `enable_user_directory` site setting.

## CrowdSec analysis

[CVE-2026-26265](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-26265) is a high-severity insecure direct object reference (IDOR) vulnerability in Discourse that allows unauthenticated attackers to bypass visibility restrictions and retrieve private user field values through the directory endpoint. The flaw can enable bulk disclosure of sensitive information, including phone numbers, addresses, and other administrator-configured private profile data.

CrowdSec has been tracking this vulnerability and its exploits since 17th of September 2026.

CrowdSec has not observed any significant exploitation activity targeting CVE-2026-26265 across its network. As a result, no community-driven trend analysis is available for this vulnerability at this time.

Attackers first request `/site.json` to identify private user-field IDs, then target `/directory_items.json?period=all&user_field_ids=<id>` to bypass authorization and retrieve exposed private user-field values.

## Timeline

- 2026-02-26: CVE Published. CVE-2026-26265 is published to NVD.
- 2026-09-17: Rule Released. CrowdSec releases a rule to detect CVE-2026-26265 exploitation attempts against the CrowdSec Network.

## References

- https://github.com/discourse/discourse/security/advisories/GHSA-crxf-p6jm-vpgw
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-26265.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-26265) follows observed exploitation activity for CVE-2026-26265. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.