CVE-2026-26265 Details
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=` 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.
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Exploit prediction scoring system (EPSS) score for CVE-2026-26265
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.05 Probability of exploitation activity being observed over the next 30 days (15th percentile)
CVSS score for CVE-2026-26265
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
7.5 High
Products affected by CVE-2026-26265
Discourse 2.4.0
Discourse 2.4.2
Discourse 2.4.5
Discourse 2.5.0
Discourse 2.5.1
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
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CVE-2026-26265 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 901 48.23%
DE 244 13.06%
NL 103 5.51%
FR 82 4.39%
GB 79 4.23%
SG 71 3.80%
CA 51 2.73%
CN 40 2.14%
JP 33 1.77%
IN 32 1.71%

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CVE-2026-26265 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 1,586 96.18%
Education 20 1.21%
Telecommunications 16 0.97%
Government/Politics 9 0.55%
Business Services 5 0.30%
Finance 3 0.18%
Nonprofit/NGO 3 0.18%
Retail 3 0.18%
Insurance 2 0.12%
Engineering 2 0.12%

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